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Topic Review
Surgical Management of Pancreatic Neuroendocrine Tumours (pNETs)
Pancreatic neuroendocrine tumours (pNETs) are a group of rare neoplasms with an incidence of 1–2/100,000 inhabitants/year. They represent 2% of all pancreatic neoplasms and are characterized by a great heterogeneity according to their genetic or sporadic origin, their functional or non-functional character, their degree of locoregional or systemic invasion and their single or multiple localization. The reference curative treatment is surgical resection of the pancreatic tumor in specialized high-volume centres, after a multidisciplinary discussion involving surgeons, oncologists, radiologists and pathologists.
  • 938
  • 14 Jan 2022
Topic Review
Melanocortins Protect against Diabetes Caused by Obesity
Melanocortins, a group of cleavage peptide products of pro-opiomelanocortin (POMC), activate melanocortin receptors on the surface of a diverse range of cell types, leading to different biological actions. They are so named because of their melanotropic activity, that is, the ability of melanocortins to increase pigmentation in melanocytes in the skin and hair follicles, increase concentrations of eumelanin and prevent an increase in photosensitive pheomelanin. Melanocortins are produced by POMC neurons in the pars intermedia of the pituitary gland, the hypothalamic arcuate nucleus and the dorsal medullary nucleus of the solitary tract. They can be distinguished by the presence of an invariant amino acid sequence in each melanocortin peptide, His-Phe-Arg-Trp. The melanocortins produced in humans include alpha-melanocyte stimulating hormone (α-MSH), beta-melanocyte stimulating hormone (β-MSH), gamma-melanocyte stimulating hormone (γ-MSH) and adrenocorticotropic hormone (ACTH).
  • 938
  • 26 Feb 2024
Topic Review
Transience of the Retinal Output and Circuit Elements
Retinal ganglion cells (RGCs) encrypt stimulus features of the visual scene in action potentials and convey them toward higher visual centers in the brain. Although there are many visual features to encode, the recent understanding is that the ~46 different functional subtypes of RGCs in the retina share this task. In this scheme, each RGC subtype establishes a separate, parallel signaling route for a specific visual feature (e.g., contrast, the direction of motion, luminosity), through which information is conveyed. The efficiency of encoding depends on several factors, including signal strength, adaptational levels, and the actual efficacy of the underlying retinal microcircuits. Upon collecting inputs across their respective receptive field, RGCs perform further analysis (e.g., summation, subtraction, weighting) before they generate the final output spike train, which itself is characterized by multiple different features, such as the number of spikes, the inter-spike intervals, response delay, and the rundown time (transience) of the response. These specific kinetic features are essential for target postsynaptic neurons in the brain in order to effectively decode and interpret signals, thereby forming visual perception.
  • 938
  • 11 Mar 2022
Topic Review
Carbazole Derivatives as STAT Inhibitors
The carbazole class is made up of heterocyclically structured compounds first isolated from coal tar. Their structural motif is preponderant in different synthetic materials and naturally occurring alkaloids extracted from the taxonomically related higher plants of the genus Murraya, Glycosmis, and Clausena from the Rutaceae family. Concerning the biological activity of these compounds, many research groups have assessed their antiproliferative action of carbazoles on different types of tumoral cells, such as breast, cervical, ovarian, hepatic, oral cavity, and small-cell lung cancer, and underlined their potential effects against psoriasis.
  • 937
  • 09 Aug 2021
Topic Review
Platforms for Protein-Based Vaccines
To date, vaccination has become one of the most effective strategies to control and reduce infectious diseases, preventing millions of deaths worldwide. The earliest vaccines were developed as live-attenuated or inactivated pathogens, and, although they still represent the most extended human vaccine types, they also face some issues, such as the potential to revert to a pathogenic form of live-attenuated formulations or the weaker immune response associated with inactivated vaccines. Advances in genetic engineering have enabled improvements in vaccine design and strategies, such as recombinant subunit vaccines, have emerged, expanding the number of diseases that can be prevented. Moreover, antigen display systems such as VLPs or those designed by nanotechnology have improved the efficacy of subunit vaccines. Platforms for the production of recombinant vaccines have also evolved from the first hosts, Escherichia coli and Saccharomyces cerevisiae, to insect or mammalian cells. Traditional bacterial and yeast systems have been improved by engineering and new systems based on plants or insect larvae have emerged as alternative, low-cost platforms. Vaccine development is still time-consuming and costly, and alternative systems that can offer cost-effective and faster processes are demanding to address infectious diseases that still do not have a treatment and to face possible future pandemics.
  • 935
  • 06 Aug 2021
Topic Review
HARE/Stabilin-2
The Stabilin receptors are a two-member family in the type H class of scavenger receptors. These dynamic receptors bind and internalize multiple ligands from the cell surface for the purpose of clearing extracellular material including some synthetic drugs and for sensing the external environment of the cell. Stabilin-1 was the first receptor to be cloned, though the biological activity of Hyaluronic Acid Receptor for Endocytosis (HARE)/Stabilin-2 was observed about 10 years prior to the cloning of Stabilin-1. Stabilin-1 has a more diverse expression profile among the tissues than HARE/Stabilin-2. 
  • 932
  • 28 Jul 2021
Topic Review
Ocular Toxoplasmosis
Ocular toxoplasmosis (OT) is an ocular disease caused by infection of the eye with the parasite Toxoplasma gondii and it is the most common cause of eye inflammation in the world.
  • 926
  • 25 May 2021
Topic Review
RNA Modifications
RNA modifications are diverse post-transcriptional modifications that regulate RNA metabolism and gene expression. RNA modifications, and the writers, erasers, and readers that catalyze these modifications, serve as important signaling machineries in cellular stress responses and disease pathogenesis.
  • 926
  • 14 May 2021
Topic Review
Bone Marrow as memory organ
The bone marrow (BM) is key to protective immunological memory because it harbors a major fraction of the body’s plasma cells, memory CD4+ and memory CD8+ T-cells. Despite its paramount significance for the human immune system, many aspects of how the BM enables decade-long immunity against pathogens are still poorly understood. In this review, we discuss the relationship between BM survival niches and long-lasting humoral immunity, how intrinsic and extrinsic factors define memory cell longevity and show that the BM is also capable of adopting many responsibilities of a secondary lymphoid organ. Moreover, we discuss what factors determine the establishment of long-lasting immunological memory in the BM and what we can learn for vaccination technologies and antigen design. Finally, we touch on how a more holistic understanding of the BM is necessary for the development of modern and efficient vaccines against the pandemic SARS-CoV-2.
  • 925
  • 24 Jun 2021
Topic Review
Microplastics Effects on Aquatic Fauna Vascular System
Plastic abandoned in the environment is prone to segregation, leading to the generation of microplastics (MPs) and nanoplastics (NPs), which can reach aquatic and terrestrial organisms. MPs/NPs in water can access fish’s bodies through the gills, triggering an inflammatory response in loco. Furthermore, from the gills, plastic fragments can be transported within the circulatory system altering blood biochemical parameters and hormone levels and leading to compromised immunocompetence and angiogenesis. In addition, it was also possible to observe an unbalanced ROS production, damage in vascular structure, and enhanced thrombosis. MPs/NPs led to cardiotoxicity, pericardial oedema, and impaired heart rate in fish cardiac tissue. MPs/NPs effects on aquatic organisms pose serious health hazards and ecological consequences because they constitute the food chain for humans. Once present in the mammalian body, plastic particles can interact with circulating cells, eliciting an inflammatory response, with genotoxicity and cytotoxicity of immune cells, enhanced haemolysis, and endothelium adhesion.
  • 920
  • 08 Feb 2023
Topic Review
Hop-Derived Bitter Acids
In this entry, we introduce the effects and underlying mechanisms of hop-derived bitter acids found in beer. Iso-α-acids (IAAs), the main bitter components of beer, enhance hippocampus-dependent memory and prefrontal cortex-associated cognitive function via dopamine neurotransmission activation. Matured hop bitter acids (MHBAs), oxidized components with β-carbonyl moieties derived from aged hops, also enhance memory functions via norepinephrine neurotransmission-mediated mechanisms. Furthermore, the effects of both IAAs and MHBAs are attenuated by vagotomy, suggesting that these bitter acids enhance cognitive function via vagus nerve stimulation. Moreover, supplementation with IAAs attenuates neuroinflammation and cognitive impairments in various rodent models of neurodegeneration including Alzheimer’s disease. Daily supplementation with hop-derived bitter acids (e.g., 35 mg/day of MHBAs) may be a safe and effective strategy to stimulate the vagus nerve and thus enhance cognitive function.
  • 919
  • 09 Jul 2021
Topic Review
Cellular functions of OCT-3/4
Octamer-binding transcription factor 3/4 (OCT-3/4), which is involved in the tumorigenesis of somatic cancers, has diverse functions during cancer development. Overexpression of OCT-3/4 has been detected in various human somatic tumors, indicating that OCT-3/4 activation may contribute to the development and progression of cancers. Stem cells can undergo self-renewal, pluripotency, and reprogramming with the help of at least four transcription factors, OCT-3/4, SRY box-containing gene 2 (SOX2), Krüppel-like factor 4 (KLF4), and c-MYC. Of these, OCT-3/4 plays a critical role in maintenance of undifferentiated state of embryonic stem cells (ESCs) and in production of induced pluripotent stem cells (iPSCs). Stem cells can undergo partitioning through mitosis and separate into specific cell types, three embryonic germ layers: the endoderm, the mesoderm, and the trophectoderm. It has been demonstrated that the stability of OCT-3/4 is mediated by the ubiquitin-proteasome system (UPS), which is one of the key cellular mechanisms for cellular homeostasis. The framework of the mechanism is simple, but the proteolytic machinery is complicated. Ubiquitination promotes protein degradation, and ubiquitination of OCT-3/4 leads to regulation of cellular proliferation and differentiation. Therefore, it is expected that OCT-3/4 may play a key role in proliferation and differentiation of proliferating cells.
  • 918
  • 22 Sep 2021
Topic Review
Rodent Models of Audiogenic Epilepsy
Animal models of epilepsy are of great importance in epileptology. They are used to study the mechanisms of epileptogenesis, and search for new genes and regulatory pathways involved in the development of epilepsy as well as screening new antiepileptic drugs. Many methods of modeling epilepsy in animals are used, including electroconvulsive, pharmacological in intact animals, and genetic, with the predisposition for spontaneous or refractory epileptic seizures. Due to the simplicity of manipulation and universality, genetic models of audiogenic epilepsy in rodents stand out among this diversity.
  • 917
  • 31 Jan 2023
Topic Review
Herpes Zoster in Antiretroviral Therapy
The incidence of herpes zoster (HZ) in patients infected with HIV is higher than that of the general population. However, the incidence of HZ in HIV patients receiving antiretroviral therapy (ART) remains unclear.
  • 916
  • 08 Jun 2021
Topic Review
Susceptibility to Head and Neck Cancers
HNC involves a series of tumors originating in the oropharynx, hypopharynx, oral cavity, lip, larynx, or nasopharynx. Smoking, alcohol consumption, and high-risk human papillomaviruses have been related to HNC. In connection with the role of genetics in HNC, several recent meta-analyses have reported the association of polymorphisms with the risk of HNCs.
  • 916
  • 22 Oct 2021
Topic Review
MiR-7
miR-7 is an ancient miRNA involved in the fine-tuning of several signaling pathways, acting mainly as tumor suppressor. Through downregulation of PI3K and MAPK pathways, its dominant role is the suppression of proliferation and survival, stimulation of apoptosis and inhibition of migration. Besides these functions, it has numerous additional roles in the differentiation process of several cell types, protection from stress and chromatin remodulation. In the brain, one of the most investigated tissues, its downregulation is linked to glioblastoma cell proliferation. miR-7 deregulation is found also in other tumor types, such as liver, lung and pancreas. In some types of lung and oral carcinoma, it can act as oncomir. However, the miR-7 roles in cell fate determination and maintenance of cell homeostasis are still to be fully discovered, as well as the possibilities of its use as a specific biotherapeutic.
  • 915
  • 17 May 2021
Topic Review
Type II Transmembrane Serine Proteases in Adipose Tissue
Adipose tissue is a crucial organ in energy metabolism and thermoregulation. Adipose tissue phenotype is controlled by various signaling mechanisms under pathophysiological conditions. Type II transmembrane serine proteases (TTSPs) are a group of trypsin-like enzymes anchoring on the cell surface. These proteases act in diverse tissues to regulate physiological processes, such as food digestion, salt-water balance, iron metabolism, epithelial integrity, and auditory nerve development. Several members of the TTSP family, namely, hepsin, matriptase-2, and corin, have been shown to play a role in regulating lipid metabolism, adipose tissue phenotype, and thermogenesis, via direct growth factor activation or indirect hormonal mechanisms. In mice, hepsin deficiency increases adipose browning and protects from high-fat diet-induced hyperglycemia, hyperlipidemia, and obesity. Similarly, matriptase-2 deficiency increases fat lipolysis and reduces obesity and hepatic steatosis in high-fat diet-fed mice. In contrast, corin deficiency increases white adipose weights and cell sizes, suppresses adipocyte browning and thermogenic responses, and causes cold intolerance in mice. These findings highlight an important role of TTSPs in modifying cellular phenotype and function in adipose tissue. 
  • 913
  • 02 Aug 2023
Topic Review
Multimodal Communication in Plant Environment
Stink bugs use semiochemicals to communicate over long distances and exchange vibratory signals that are transmitted on plants over shorter distances. These signals are produced by various mechanisms, such as body vibration (tremulation) or drumming on the substrate, and are accompanied by visual, chemical, and mechanical signals and cues when they encounter a mate.
  • 912
  • 07 Jan 2022
Topic Review
Phytoremediation of Cadmium
Cadmium (Cd) is one of the most toxic metals in the environment, and has noxious effects on plant growth and production. Cd-accumulating plants showed reduced growth and productivity. Therefore, remediation of this non-essential and toxic pollutant is a prerequisite. Plant-based phytoremediation methodology is considered as one a secure, environmentally friendly, and cost-effective approach for toxic metal remediation. Phytoremediating plants transport and accumulate Cd inside their roots, shoots, leaves, and vacuoles. Phytoremediation of Cd-contaminated sites through hyperaccumulator plants proves a ground-breaking and profitable choice to combat the contaminants. 
  • 911
  • 05 Aug 2021
Topic Review
Rosemary Infusions
Rosemary (Rosmarinus officinalis L., Lamiaceae family) is quite appreciated in worldwide gastronomy due to its aromatic flavor and preservative properties. In addition, this plant is also traditionally consumed in the infusion form aiming at the treatment and prevention of several health disorders, such as dyspepsia, mild spasmodic disorders, headache, depression, anxiety, respiratory disorders, minor peripheral circulatory disorders, and minor muscular and articular pain.
  • 910
  • 12 May 2021
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