Endurance-sport athletes have a high incidence of gastrointestinal disorders, compromising performance and impacting overall health status. An increase in several proinflammatory cytokines and proteins  has been observed in ultramarathoners and triathlon athletes. One of the most common effects of this type of physical activity is the increase in intestinal permeability, known as leaky gut. The intestinal mucosa's degradation can be identified and analyzed by a series of molecular biomarkers, including the lactulose/rhamnose ratio, occludin and claudin (tight junctions), lipopolysaccharides, and I-FABP. Identifying the molecular mechanisms involved in the induction of leaky gut by physical exercise can assist in the determination of safe exercise thresholds for the preservation of the gastrointestinal tract. It was recently shown that 60 min of vigorous endurance training at 70% of the maximum work capacity led to the characteristic responses of leaky gut. It is believed that other factors may contribute to this effect, such as altitude, environmental temperature, fluid restriction, age and trainability. On the other hand, moderate physical training and dietary interventions such as probiotics and prebiotics can improve intestinal health and gut microbiota composition. This review seeks to discuss the molecular mechanisms involved in the intestinal mucosa's adaptation and response to exercise and discuss the role of the intestinal microbiota in mitigating these effects. Physical exercise is a non-pharmacologic agent in preventing and managing non-communicable chronic diseases, where its beneficial effect is well-documented in the musculoskeletal and cardiovascular systems. In addition to these systems, physical exercise also promotes positive adaptations in the gastrointestinal tract, such as a decrease in colon cancer risk . HoweverExercise-induced gastrointestinal syndrome results from two distinct and communicable pathways: The circulatory-gastrointestinal pathway and the neuroendocrine-gastrointestinal pathway. The first pathway redistributes blood flow to working muscles and peripheral circulation, reducing total splanchnic perfusion, while the neuroendocrine-gastrointestinal pathway is related to the increase in sympathetic activation and the consequent reduction in the gastrointestinal functional capacity , 6. Thus2max) may not be limited to the gastrointestinal system and the intestinal microbiota, affecting its structure and functionality. Deterioration of the gastrointestinal mucosal barrier may also occur, increasing its permeability to bacterial endotoxins, and low-grade systemic inflammation may not only affect gastrointestinal homeostasis but also overall health  during exercise , an intestinal biomarker of enterocyte damage and ischemia . The incThe increase in intestinal permeability also allows LPS to pass into the bloodstream. This increase in the concentration of LPS in the blood occurs in exercise with short duration (<20 min) , long >, 39, andAfter exploring the main molecular changes caused by exercise, the next topic aims to highlight whether it is possible to determine an exercise “threshold” that leads to the “leaky gut” phenomenon.While low-to-moderate intensity is associated with positive effects on the gastrointestinal tract, including mucosa preservation and improved intestinal motility, ischemia and hypoperfusion associated with strenuous exercise are commonly associated with reduced gastric motility, epithelial injury, disturbed mucosa integrity, enhanced permeability, impaired nutrient absorption, and endotoxemia with local and systemic low-grade inflammation  Figure . It is tNaturally, it should be noted that different exercise stimuli may lead to adverse impacts on the intestine, also considering their intensity and duration, and the environmental conditions in which they take place. It is known that high altitudes can have adverse effects on the small intestine , 44 and The increase in intestinal permeability has already been identified in several types of exercise: cycling , swimmin2Peak leads to an enhanced lactulose/rhamnose ratio, compared to lower intensities of 40 and 60% of the VO2Peak ] and cold , led to the same alteration in intestinal permeability compared to control . The hot environment group had a significant increase in blood LPS, indicating the effect of exercise-induced endotoxemia  raised I-FABP levels in a similar way  accelerates gastric emptying and may decrease the risk for Gastroesophageal Reflux Disease (GERD) (2max)  . It was e (GERD) , reducine (GERD) . A simil) (2max) . Even an) (2max) . These o2max or a greater decrease in total fat mass  may lead to injury and increased intestinal permeability. Depending on variables such as temperature, moderate to prolonged exercise (>60 min) can also lead to intestinal injury, based on elevations in the circulating I-FABP . It is sfat mass , 79. ThuThe gut microbiota's responsiveness to external factors has received much attention in recent years due to these changes' clinical potential effects on the host's health. Among these factors, dietary intervention and physical exercise are recurrent elements in studies involving the GM's composition and its systemic impacts across different tissues and physiologic systems . NaturalAs previously described, prolonged and excessive exercise stimuli may affect the gastrointestinal environment, impacting the mucosa's integrity and increasing its permeability to external agents such as endotoxins. This process is associated with the onset of proinflammatory signaling, affecting gastrointestinal health. Dehydration, bloody diarrhea episodes, and abdominal discomfort are typical responses in endurance athletes . These eUnlike what is observed in response to strenuous exercise stimuli, certain intensities positively modify the GM's quality and function, favoring the host's health. In this way, a body of evidence has shown that exercise is a potent modulator of intestinal microbiota composition and function, leading to enrichment and bacterial proliferation, improvement of intestinal barrier integrity, and the synthesis of immunomodulatory and antimicrobial agents . Moderatlamina propria  and histone activation deacetylases (HDAC) in leucocyte endothelial cells. SCFAs can bind to Gpr43  and reduce inflammatory responses of neutrophils and eosinophils and be capable of inhibiting HDAC, preventing colorectal cancer , 95. In Veillonella atypica isolated from a marathon runner was shown to increase the submaximal running time to exhaustion on mice. Considering that Veillonella atypica metabolizes lactate into propionate and acetate through the methyl malonyl-CoA pathway, it is speculated that the lactate produced during exercise is converted into SCFAs, improving exercise capacity  with a progression of intensities and volumes of exercise. Obviously, confounding factors such as temperature, altitude, dehydration and degree of trainability need to be controlled for. Thus, more studies are needed in order to emphasize the role of exercise in intestinal permeability and to pinpoint other variables that may influence this phenomenon at the time of activity.FR, BP, and GM: writing of the manuscript and elaboration of the figures. LHK: writing of the manuscript. OF: writing of the manuscript and general review. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by hematopoietic stem-cell-derived clonal proliferation, leading to bone marrow (BM) fibrosis. Hematopoiesis alterations are closely associated with modifications of the BM microenvironment, characterized by defective interactions between vascular and endosteal niches. As such, neoangiogenesis, megakaryocytes hyperplasia and extensive bone marrow fibrosis, followed by osteosclerosis and bone damage, are the most relevant consequences of PMF. Moreover, bone tissue deposition, together with progressive fibrosis, represents crucial mechanisms of disabilities in patients. Although the underlying mechanisms of bone damage observed in PMF are still unclear, the involvement of cytokines, growth factors and bone marrow microenvironment resident cells have been linked to disease progression. Herein, we focused on the role of megakaryocytes and their alterations, associated with cytokines and chemokines release, in modulating functions of most of the bone marrow cell populations and in creating a complex network where impaired signaling strongly contributes to progression and disabilities. Primary myelofibrosis (PMF), known as a clonal stem cell disorder, is a chronic myeloproliferative syndrome representing the rarest and most complex of all BCR-ABL-negative myeloproliferative neoplasms (MPNs), a group of neoplastic hematological diseases comprising essential thrombocythemia (ET) and polycythemia vera (PV). From a genetic point of view, the vast majority of patients show the JAK2V617F driver mutation; the remaining population of patients usually shows either calreticulin (CALR) mutations or thrombopoietin receptor mutations  ,4. TheseOvert PMF is the least common  of MPN dBone marrow represents a complex and heterogenous microenvironment in which physiological homeostasis and cellular activities are based on continuous crosstalk between hematopoietic and stromal niches, in close communication throughout environmental signals, growth factors, adhesion molecules and the vascular network. The stem area is composed of stem precursors and endosteal bone surface, in which resident hematopoietic stem cells (HSCs) proliferate and differentiate . OsteoblPMF complexity is mainly due to the onset of bone marrow fibrosis, followed by a long sequence of cascade events. This results in hematopoiesis impairment and organ failure, culminating in osteosclerotic deposition during the late stage of the disease, which seriously impairs the health of affected patients . Thus, f+Flt3+ cells expressing the CD41 megakaryocyte antigen [Altered megakaryocytes produce a plethora of growth factors, interleukins and cytokines involved in the onset of a dysfunctional microenvironment, contributing to the neoangiogenesis and hyperactivation of both fibroblasts and osteoblasts . The fun antigen . Among t antigen . However antigen . In factBone modifications are a pathognomonic hallmark of PMF since they represent one of the direct results of bone marrow disruption. Osteosclerosis remains the most common bone change, which represents a pathological event characterized by increased bone density and abnormal hardening ,59,60, aBone tissue homeostasis is controlled by the cooperation of both HSCs and MSCs, involved in the differentiation in osteoclasts (OCs) and osteoblasts (OBs), respectively. OBs share their mesenchymal biogenesis with chondrocytes, adipocytes and stromal cells ,64,65,66It is well established that osteosclerotic evolution in PMF is mainly due to the failure of the bone formation and bone resorption balance, and OBs and OCs represent the main characters of osteosclerosis pathogenesis. On the one hand, OBs are strongly induced to proliferate and differentiate ; on the Osteosclerosis associated with MPNs is a pathological evolution, typical of the advanced stage of myelofibrosis, which is due to the gradual replacement of marrow by collagen and bone trabeculae accomplished by activated myofibroblasts  . These tMuch evidence has been reported to support the role of osteoprotegerin (OPG) as a substantial marker involved in PMF pathogenesis ,103. PlaPMF is a myeloproliferative syndrome with a very complex clinical background, characterized by general bone marrow failure with impaired hematopoiesis followed by extramedullary hematopoiesis, splenomegaly and progressive bone deposition replacing the fibrotic areas. Bone tissue deposition remains one of the mechanisms, together with fibrosis, associated with unavoidable progression. Although several mechanisms of PMF bone damage remain unknown, the involvement of many biomarkers and cell lineages constitutively present in the bone marrow microenvironment has been confirmed. Assuming that the physiological state of bone marrow is based on the continuous balance between the hematopoietic niche and bone remodeling, it is necessary to evaluate the most important factors involved in bone impairment and osteosclerosis. In particular, we summarized the central role of megakaryocytes and their alterations associated with the release of a plethora of cytokines and chemokines. Each of them represents a relevant factor, the activity of which seems to be absolutely interconnected with each bone marrow cell population, creating a network of impaired signaling that contributes to the overall imbalance of the bone marrow system. In this complex system, each cell line, associated with a specific panel of cytokines and signals, contributes to bone alterations and modifies the physiological functions, affecting the fine balance between OBs and OCs and, in turn, affecting bone formation and bone resorption homeostasis.


Targeted and immunological therapies have become the gold standard for a large portion of non-small cell lung cancer (NSCLC) patients by improving significantly clinical prognosis. However, resistance mechanisms inevitably develop after a first response, and almost all patients undergo progression. The knowledge of such a resistance mechanism is crucial to improving the efficacy of therapies. So far, monitoring therapy responses through liquid biopsy has been carried out mainly in terms of circulating tumor (ctDNA) analysis. However, other particles of tumor origin, such as extracellular vehicles (EVs) represent an emerging tool for the studying and monitoring of resistance mechanisms. EVs are now considered to be ubiquitous mediators of cell-to-cell communication, allowing cells to exchange biologically active cargoes that vary in response to the microenvironment and include proteins, metabolites, RNA species, and nucleic acids. Novel findings on the biogenesis and fate of these vesicles reveal their fundamental role in cancer progression, with foreseeable and not-far-to-come clinical applications in NSCLC. EGFR and ALK genes, as well as for patients with alterations in the proto-oncogene tyrosine-protein kinase ROS-1 (ROS1) [In the last ten years, treatment of non-small cell lung cancer (NSCLC) has been revolutionized by the introduction of targeted and immunological therapies in clinical practice ,2,3. Cur1 (ROS1) . On the 1 (ROS1) . Althoug1 (ROS1) . Current1 (ROS1) .EVs are defined as a heterogeneous group of membrane-delimited nanosized particles actively released by any cell type, including cancer cells . A definIn this review, we will give particular attention to EVs of endosomal origin (defined as exosomes) and plasma membrane-derived microparticles (microvesicles) . ExosomeEVs are a group of membranous structures that can be actively released by any cell, which are highly heterogeneous for their origins and content, and are considered to be ubiquitous mediators of intercellular communication . TypicalExosome cargoes reach their destination either from the Golgi or by internalization from the plasma membrane, before being sorted to the intraluminal vesicles (ILV) that are formed by the inward of endosomal membrane of the multivesicular bodies (MVBs) and are ultimately secreted upon fusion with the cell surface . Thus, eThe presence of DNA inside EVs depends on methodological drawbacks that are not completely clear . Short DAfter loading of their cargo, ILVs are targeted by the plasma membrane to be released as exosomes through the specific involvement of the ESCRT-1 component tumor susceptibility gene 101 protein (TSG101) and RAS-related protein (RAB) GTPases, while fusion with the cell membrane is guided by the soluble NSF attachment protein receptor (SNARE) complex ,22.Microvesicles follow a different route of biogenesis, which takes place at the level of discrete microdomains of lipids and membrane-associated proteins that cluster within the plasma membrane after the induction of local changes in Ca2+ concentration . These eThe fate of EVs depends on the specific composition of surface receptors that will target them to the right cell type. EVs can remain bound to the plasma membrane through tetraspanin-guided interaction with integrins while waiting for their cargo to be released, initiate signaling transduction, or engage the antigen presentation pathways . EV fusiThe interdependence of the intracellular machineries required for release and internalization of both exosomes and microvesicles facilitates the development of shared mechanism of deregulation that can be adopted by cancer cells to take over the secretome apparatus . A tumorApoptotic bodies are a less diffuse type of EVs, with a broad size range of 50 nm to 2 μm . These EEVs are lipid-bilayer containers of a variety of biologically active signaling molecules, proteins, nucleic acids, functional lipids, and metabolites that are scheduled for secretion in the extracellular space in response to the microenvironment . The carCargoes are considered the first regulators of EV formation, when the future fate of a particular vesicle is being determined . Hence, Isolation of EVs from plasma of early stage NSCLC patients and subsequent miRNA-seq profiling, can define, with increased diagnostic accuracy, patient-specific subsets of miRNAs that are more expressed in lung cancer patients, compared with healthy individuals ,51. In fBesides the functional delivering of their molecular content to recipient cells, EVs can be seen as signalosomes of several cellular processes, from the activation of cell surface receptor pathways or the transfer of membrane-associated molecules, including immunogenic antigens . De factInduction of immunosuppression is intimately related to oncogenic progression through the development of adaptive mechanisms that bypass inhibitory action of proliferative pathways. In a context of active immune surveillance, there is a selective pressure for cancer cells to either downregulate neoantigen presentation or induce an immunosuppressive microenvironment . In the During therapy, immune escape in NSCLC evolves through a multistep process visible at the level of DNA mutations in MHC genes, epigenome, and changes in RNA expression of immune regulatory genes ,66. AcquEvery tumor that has grown to a considerable size has also somehow escaped immune surveillance, which is the prerequisite for cancer cells to colonize distant sites. Tumor EVs might trigger adaptive immune responses or suppress inflammation, depending on the status of a particular immune cell, shaping in this way the evolution of metastases under the selective pressure of the immune system. A primary tumor can seed out immunosuppressive EVs to remotely prepare the metastatic niche for the homing of cancer cells. Fusion of EVs with the recipient plasma membrane is regulated by the presence of specific docking proteins, receptors, and integrins. Vesicles released by cancer cells that have evaded the immune system can be targeted to favorite organs and, given the integrin pattern they present on the surface, promote the premetastatic niche of the specific cancer-cell type from which they have originated ,75. OrgaThe metastatic propensity of a primary tumor can also be inferred by the analysis of the vesicular RNA cargo . A multiWith the increasing knowledge of molecular biology and genetics of tumors, the research and clinical application of targeted therapy has become a hot topic, with the aim of improving prognosis and guiding therapeutic decision by understanding the emerging of therapeutic resistance . Each siEVs, found in the circulation of cancer patients refractory to therapy, can also transport nucleic acids molecules of wild-type EGFR and mutated EGFR that reflect the genetic signature of the original tumor . Howeverhttps://clinicaltrials.gov/). Liquid biopsy of cancer patients can provide a comprehensive overview of tumor heterogeneity to help with diagnosis and guide patient care. Regulatory agencies in Europe and the United States have approved liquid biopsy tests in clinical routine for the detection of EGFR mutations on ctDNA in plasma of patients with NSCLC [Over the past five years, explorative approaches for integrating liquid biopsy into the management of most common cancer types have been developed at a rapid rate , with ovth NSCLC , with thth NSCLC . Althougth NSCLC .Despite the substantial technical advances, the complexity associated with the enrichment of single or multiple EV subtypes with different composition poses continuous challenges to avoiding method-dependent bias. Methods for isolation from body fluids and analysis of EVs comprise separation on microfluidics, by density gradients, or through size exclusion chromatography, which can be followed by immunoprecipitation for further enrichment of specific subpopulations of EVs ,111,112.Clinical application of EV-based diagnostics in NSCLC can be particularly helpful in the detection of oncogene mutations that confer sensitivity to specific drugs or are selected in those patients that develop pharmacological resistance. Tumor-released EVs can also help the early detection of clones that will develop immune escape through the overexpression of PD-L1 or the production of immunosuppressive miRNAs. Moreover, by defining tumor-specific miRNA signatures, EV content analysis can provide direct information on the dynamic transformation of a tumor mass and its clonal outgrowth ,115. ComCompared to exosomes, which clearly show an enrichment of specific miRNA contents that are distinct from the cellular pool, microvesicles more closely reflect the source cell transcriptome, being particularly enriched in mRNA sequences . Larger To date, most available protocols to recover EVs from patients’ blood resulted in the recovery of a heterogeneous population of vesicles of uncertain origin, but the implementation of more robust technologies have facilitated the isolation of specific subpopulations of as few as ten EVs per microliter of plasma with direct impact on the performance of revealing predictive biomarkers . Novel aAs a vehicle of extracellular RNA, EVs could be a considered as an easily accessible reservoir of biomarkers discovery  and moleImprovement of efficient and cost-effective methodologies for separation of exosomes and microvesicles population from the background of non-EV particles, based on their surface proteome composition, can foster the ultrasensitive detection of cancer-specific mutations on mRNA that could implement classical ctDNA blood analysis ,124. At In the wake of assigning an integrative view of the heterogeneity of resistance mechanisms, it is mandatory for to have an implementation of protocols that can assess the ongoing patient mutational status almost real time for the allocation of the specific therapies. Liquid biopsy poses as the best choice for the non-invasive monitoring of emerging resistance mechanisms at different time points, , which cannot be captured by conventional tissue biopsy. In most cases, measurement of ctDNA has permitted to recover substantial information about the onset of resistance mutations in NSCLC, even much before clinical progression. To achieve the highest grade of sensitivity, however, it is understandable that the measurement of ctDNA must be incorporated with more deviceful techniques. The discovery of the ubiquitous presence of EVs in the body fluids, coupled with the development of ever more reliable and low-cost technologies for the isolation of EVs and the implementation in the purification of their content promise to provide a substantial improvement in the detection of tumor markers, from routine blood draws. Emission of immunosuppressive organ-specific EVs from the primary tumor can be a precondition to prepare distant sites for metastatic invasion, and sensitive methodologies for tumor EV isolation and analysis can constitute a new frontier of cancer diagnostic to predict the metastatic spread and therapy outcome. Several challenges should be overcome for a possible implementation of EVs in the clinical practice, with the first and foremost challenge being the standardization of the methodologies for EVs isolation and purification from plasma. These methodologies should be easily usable by molecular diagnostic laboratories, with a low turnaround time and a low cost.


The novel coronavirus (SARS-CoV-2) infection (COVID-19) has raised considerable concern on the entire planet. On March 11, 2020, COVID-19 was categorized by the World Health Organization (WHO) as a pandemic infection, and by March 18, 2020, it has spread to 146 countries. The first internal defense line against numerous diseases is personalized immunity. Although it cannot be claimed that personalized nutrition will have an immediate impact on a global pandemic, as the nutritional interventions required a long time to induce beneficial outcomes on immunity development, nutritional strategies are still able to clarify and have a beneficial influence on the interplay between physiology and diet, which could make a positive contribution to the condition in the next period. As such, a specific goal for every practitioner is to evaluate different tests to perceive the status of the patient, such as markers of inflammation, insulin regulation, and nutrient status, and to detect possible imbalances or deficiencies. During the process of disease development, the supplementation and addition of different nutrients and nutraceuticals can influence not only the viral replication but also the cellular mechanisms. It is essential to understand that every patient has its individual needs. Even though many nutrients, nutraceuticals, and drugs have beneficial effects on the immune response and can prevent or ameliorate viral infections, it is essential to detect at what stage in COVID-19 progression the patient is at the moment and decide what kind of nutrition intervention is necessary. Furthermore, understanding the pathogenesis of coronavirus infection is critical to make proper recommendations. Coronaviridae is one of the families of viruses that are known to cause diseases in birds and mammals ranging from the common cold to severe acute respiratory syndrome (SRAS). A new species that belongs to this family emerged in late 2019, causing an outbreak of a respiratory disease in the eastern part of Asia. The first species of coronavirus infecting humans (229E) was observed in 1931 and isolated first in 1965. Ultimately, the virus has evolved into the novel coronavirus (2019-n-CoV).Regarding the current situation of the COVID-19 pandemic, in which there is no optimal vaccination or cure, the functionality and efficiency of the immune response is the key factor in the defense against viral infections. Several nutrients, especially vitamins and microelements, are crucial for the immune system to function normally . In patiIn the literature, several micronutrients, herbal therapeutics, and probiotics were reported to have positive effects in both treatment and prophylaxis of viral infections . Also, vRegarding the COVID-19, it is fundamental to demonstrate the data on increasing the immune response to viral infections. The present review paper principally subjects influenza-like viral infections. Nonetheless, other viral infections have also been taken into consideration. Therefore, practical recommendations on using nutrients for the prevention and therapy of COVID-19 are given. Accordingly, the aim of this review was to provide a complementary overview of the recently available scientific literature on the strategy of using nutraceuticals in boosting the immune system under the COVID-19 pandemic. Emphasis is placed on the supplementations of nutraceuticals, probiotics, vitamins, and trace elements.Two to 14 days after exposure to the virus, the usual clinical signs are dry cough and shortness of breath. The Centers for Disease Control and Prevention (CDC) reported that the appearance of fever, chills, myalgia, headache, as well as the loss of smell and taste, could indicate an infection. The majority of humans have mild symptoms if any occur, and it has been reported that ca. 80% of infected people do not need hospitalization .Nevertheless, in some individuals, the infection can cause severe problems. With aging, the immune response becomes weaker (immunosenescence), and the levels of inflammatory mediators in the blood increases (inflammageing). The high-risk group of COVID-19 that are clinically vulnerable includes primarily elderly individuals and those with inflammation-associated conditions such as overweight and obesity, chronic obstructive pulmonary disease, cardiovascular diseases, diabetes, kidney disease, etc. The majority of severe COVID-19 cases and mortalities were within the abovementioned group of individuals, although it is worrisome that younger and healthy individuals are showing up in this cohort , 15.The virus rapidly multiplies and infects the surrounding cells throughout the respiratory system. At the time the virus gets to the lungs, an inflammatory process starts in the mucous membranes and damages the alveoli, which have difficulties in supplying oxygen, resulting in breathing difficulties. This can cause swelling in the lungs, which can result in the accumulation of fluids and dead cells and, finally, severe pneumonia. The infection can spread through mucous membranes of the body, such as the digestive system. In some cases, gastrointestinal symptoms like diarrhea, indigestion, and vomiting have been reported along with respiratory symptoms, and studies propose the possibility of fecal–oral transmission . The typSARS-CoV-2 has been isolated from the brainstems of positive patients, which indicates that this virus has common pathways of transmission with other coronaviruses that can spread through synapse-connected routes from the lung and airways. The virus can cause problems in different parts of the body, such as the heart, liver, and kidneys, particularly in the later stage of the disease. Fatal cases of COVID-19 can be caused by multiple organ failure, especially in individuals with genetic immune factors , 18.This review highlights the nutritional interventions to increase the immune response in the body during viral infections, especially considering the novel coronavirus pandemic. Due to their beneficial effects on general healthcare and disease prophylaxis, nutraceuticals have been gaining more and more importance lately . Nutrace−2  with a score of <3 points, showing low qualities of methodology. Such studies were not ignored, mainly since a meta-analysis was not done for pooled estimates. On the other side, 24 types of research (>54%) had a score >3, which suggests a valuable methodology. Although it is well-known that exercise is a very active booster of immunity , whereasin vivo and in vitro researches on animals have investigated the antiviral properties of trace elements, vitamins, and other nutraceuticals  should reduce at least 5% of the weight of the body  supplement . To incrthe body . Diabetethe body  by havinthe body .Numerous vitamins are crucial for the normal functions of the immune response . For maiMoreover, excessive amounts of vitamin E could have fatal consequences. A recent study reported that dietary supplementation with high concentrations of micronutrients and vitamins C and D is an effective and low-cost method to intensify the immune response to COVID-19 and similar respiratory diseases , 34. It The function of immune cells is also affected by vitamin D receptors, which indicates that this vitamin deeply influences the immune response to infections. The deficiency of vitamin D, mostly caused by insufficient intake, could result in weak resistance to infections and a higher incidence of various viral diseases. Concerning the COVID-19 pandemic, Ghavideldarestani et al.  reported12, has been reported  could have positive outcomes for high-risk groups of individuals (diabetes and obesity), but also during quarantine . The occreported .Such defects take place even in high-income countries and are the most common among children and infants, adolescents, the elderly, and during lactation and pregnancy . Groups 2+ cations combined with Zn ionophore pyrithione have a role in inhibition of SARS-coronavirus RNA polymerase  activity via reduction of viral replication  is an essential constituent of many important primary cell metabolites such as nucleic acids, phospholipids, lipopolysaccharides, and different cytoplasmic solutes –102. P hCalcium phosphate (CaP) in the form of microparticle or nanoparticle has been used as potential adjuvants or vaccine carrier (delivery system) for DNA and peptide vaccines for humans and mammals. CaP nanoparticles have a number of advantages over other inorganic particles. Their biodegradability and biocompatibility are excellent ; they arLactobacillus-based probiotics are recommended for the prevention of influenza-like viral infections  and rapidly replicating cells such as mucosal cells of gastrointestinal tract, colonocytes, enterocytes, macrophages, and lymphocytes. It is a glutathione precursor and could help in regulation of acid–base balance and transportation of nitrogen between body organs. It was found to increase the number of CD8+, CD4+, and T lymphocytes after bone marrow transplantation , 125. OtCandida albicans and Staphylococcus aureus, accelerate the immune responses to vaccines, and increase the titers of antibodies , which is essential for the immune system. Alagawany et al.  illustraThe diets of patients under intensive care should also be recommended by a dietician/nutritionist. Besides, to maintain the homeostasis of nutrient intake, some patients will require an oral nutrition supplement (ONS). During viral infections, the resting energy expenditure was elevated by 10%, and due to such circumstances, the energy intake has to be risen by 10% throughout the disease progression . DiabetePhytogenic feed additives exert their favorable health improving effects owing to their content of active substances such as polyphenols and secondary metabolites. Polyphenols are found in vegetables, grains, fruits, and green and black tea in different parts of the plant  to protect the plant immune system against UV radiation and pests –151.Dietary polyphenols have been reported to have various biological activities including polyphenols, which have immunomodulatory, antioxidant, anti-inflammatory, anti-allergic antimicrobial, ant- mutagenic, and detoxification activities . Recent Another example of polyphenols is resveratrol, which has been reported to have various biological properties such as immunomodulation, antioxidation, hepatoprotection, anti-inflammation, regulation of lipid metabolism, and others –160. ResIn addition to the immunomodulatory properties of polyphenol compounds, they also showed effective antioxidant properties. Polyphenols could neutralize the free radicals of both reactive oxygen species (ROS) and reactive nitrogen species (RNS), which can damage the chromosomes and consequently modify the encoded amino acid and the associated biological process . Zhong ain vivo disease models and were noticed to dramatically prevent the xanthine oxidase activity in in vitro studies  is necessary to investigate the virus pathogenicity and to perform the preclinical testing of the possible vaccines and antiviral agents. Factors that have to be considered when selecting/inventing an animal model of human coronaviruses have been reviewed . IdeallyNumerous animal prototypes have been developed for SARS and MERS caused by the respective coronaviruses , 169. ThCoronavirus spike glycoprotein (S1 domain) binds to the cognate receptor, and the S2 domain mediates viral envelope fusion with the cell membrane for the genome release into cytosol (virus uncoating process). Antibodies targeting the spike glycoprotein of coronaviruses play a critical role in inhibiting viral entry and uncoating. They have clinical potential in conferring passive immunity in the coronavirus-infected individuals.Currently, several monoclonal antibodies (both fully human molecules or humanized-version) that object the S1 receptor-binding domain (RBD) and non-RBD and S2 regions of coronaviruses have been produced and examined in cell cultures to determine the neutralizing capacity of viruses and animal models as well to assess the efficiency in prophylaxis and post-exposure stage . Such anMany compliant cell lines to human coronaviruses, including the epithelial cells of monkeys (Vero-B4 and LLC-MK2), are being utilized in the neutralization assays [inhibition of virally induced cytopathic effects (CPE) by different antibody concentrations or plaque assays] for determining the levels of neutralizing titers of the antibodies. The lung cells of goats, kidney cells of alpaca, and dromedary umbilical cord cells were identified to be permissive for MERS-CoV . MoreoveData from animal coronavirus vaccine development suggested that systemic cell-mediated or humoral immune reactions induced by parenteral management may not be enough to inhibit the virus invasion in the respiratory system . Since tImmune systems do great work in fighting foreign cells to protect the body from disease. Of course, when a global pandemic strikes the whole world, humans will feel anxious until they conquer it and be healthy. When the COVID-19 epidemic appeared, all sought to find a vaccine to counter this virus. Given a vaccine if provided, immune systems will need to adapt to the COVID-19-infected body , 41. ProThe lessons learned from this review clarified the common shared scientific knowledge between human and animal nutrition, and that knowledge gained from animal model experiences can be used as a guide in human experiments. This indicates that vitamins such as vitamins C, E, and D and some micro-minerals such as zinc, iron, and selenium and probiotics are candidates to enhance the immunity to viral infections with its specification for each virus.In conclusion, the strategies of containment have turned out not to be so effective. Such an approach did not stop the spreading of the virus. Social distancing and hygiene measures were an attempt to inhibit the transmission of the virus to give healthcare workers more time to handle the infected patients and “flatten the curve” to lower the peak and meanwhile buy time as researchers all around the world are trying to find efficient therapeutics. Even though the exact intracellular mechanisms of the immunostimulatory effects of nutraceuticals are not entirely explored, a possible beneficial effect is their anti-oxidative and anti-inflammatory activity. This review paper highlighted numerous favorable outcomes of nutraceutical usage in viral infections for both human and animal application, but based on their composition and extraction methods.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


A 36-year-old male patient presented at the Department of Maxillofacial Surgery, University Hospital Clinic Zagreb in December 2010 due to a swelling of the left body of the mandible that was noticed 4 months earlier. The patient was referred regarding an atypical clinical and radiological finding in the form of a multicystic appearance in the corpus of the left mandible and teeth mobility in the same region. A probatory biopsy was performed under local anesthesia and sent for histopathologic examination which reported odontogenic myxoma. The tumor was removed with a marginal resection of the mandible from the left first incisor to the left second molar. Two years after surgery, in January 2013, the patient was referred to the oral surgeons for implant-prosthodontic rehabilitation. Two narrow implants were placed at positions 32 and 36, and three months afterwards, implant-retained denture was made using locator connections to compensate lost teeth and to correct the ratio of soft tissues and facial contours. The patient was followed-up for 9 years without any functional and aesthetic problems. Loosing function and aesthetic morbidity, after radical surgical treatment, often have compromised the quality of life of this group of patients. It is important to highlight the need for multidisciplinary collaboration for the complete rehabilitation of the patient after surgical oncology of the maxillofacial region. Myxomas are very rare benign tumors of ectomesenchymal origin . These tDiagnosis of odontogenic myxomas is based on radiological, histopathological, and clinical findings . RadiogrThe aim of the present research is to describe a case of a 36-year-old man who developed an odontogenic myxoma of the mandible 9 years ago and successful implanto-prosthodontic rehabilitated after resective jaw surgery with a multidisciplinary approach. The purpose of this case report was to highlight the need for multidisciplinary collaboration for the complete rehabilitation of the patient after surgical oncology of the maxillofacial region.A 36-year-old male patient came to the Department of Maxillofacial Surgery, University Hospital Clinic Zagreb in December 2010 due to a swelling of the left body of the mandible that was noticed 4 months earlier. The patient did not report any other symptoms. After examination, the patient was referred to a maxillofacial surgeon regarding an atypical clinical and radiological finding in the form of a multicystic appearance (bubble-like) in the corpus of the left mandible and pathological teeth mobility in the region of the swelling. There were no enlarged lymph nodes in the neck and head area. Differential diagnosis included keratocystic odontogenic tumor, ameloblastoma, central giant cell granuloma, and odontogenic myxoma.The patient denied any systemic disease or condition and reported no previous surgeries. A general physical examination was unremarkable. The patient did not have any deleterious habits such as alcohol consumption or smoking and without previous history of swelling or trauma of the mandible. On extraoral examination, the patient displayed some facial asymmetry with an obvious firm and diffuse swelling on the left side of the mandible. The overlying skin was normal in appearance. Intraorally, there was a diffuse swelling in the buccal vestibule. Teeth in the third quadrant were without any pain sensation but with pathological mobility. Lower incisors and canine had mobility grade I and premolars and first molar grade II according to the Miller classification.The orthopantomogram (OPG) showed a multilocular radiolucency, with fine trabeculation, extending from the left canine, towards the first molar  with no In accordance with the ethical protocol of the School of Dental Medicine, University of Zagreb, Croatia, written consent was obtained from the patient before surgery in general anesthesia in January 2011. Lower incisors, canine, premolars, and first molar were extracted just before the first incision. A mucoperiosteal flap with full exposition of the buccal aspect of the tumor was performed. The tumor was removed with a marginal resection of the mandible from the left first incisor to the left second molar. The surgical site was examined and precociously cleaned of all myxomatous tissue, and a reconstruction plate was used to reinforce the resected mandible. The surgical specimen was a soft, gelatinous mass measuring approximately 1 cm in diameter, with a mucinous appearance. Histologically, the tumor was composed of randomly oriented spindle-shaped cells with long fine cytoplasmic processes, within an abundant, myxoid ground substance, containing small capillaries and fragments of bone trabecula. Odontogenic epithelium was absent, and clear margins were confirmed Figures . The patTwo years after surgery, in January 2013, the patient was referred to the Department of Oral Surgery, School of Dental Medicine, University of Zagreb for implant-prosthodontic rehabilitation. A control OPG  and clinDue to the deep bite, orthodontic therapy was started in the upper jaw, and in the lower jaw, implant-prosthodontic rehabilitation was planed with minimally invasive procedures because of the lack of a support zone and defect of soft and bone tissues. Regional nerve block anesthesia  was administered. After carefully raising the mucoperiosteal flap and isolating the mental nerve, the bone crest was expanded at the planned implant sites, with a piezosurgical bone saw , and two narrow diameter implants  were placed at positions 32 and 36 Figures  and 8. AThree months after surgery, a cover denture was made with locator connections to compensate for lost teeth and to correct the ratio of soft tissues and facial contours. No tumor recurrence was found on the follow-up OPG and CBCT for 7 years after implant placement and 9 years postresective surgery Figures 9. The patAccording to the literature , it is rClinically, the presented case showed symptoms that match all of these mentioned signs but without aggressive behavior and the lingual cortical plate was preserved.Odontogenic myxomas have been diagnosed with many different imaging features like conventional radiography such as panoramic, occlusal, and periapical, or more accurately like cone beam computed tomography/computed tomography (CBCT/CT) and magnetic resonance imaging (MRI) , 28. WanAlthough benign, odontogenic myxoma is invasive into surrounding normal bone, sometimes breaking through its boundaries . This inMicroscopically, the tumor has a mucoid-rich ECM, with scattered stellate cells, connective tissue fibers, irregular calcifications, bony trabeculae, sparse capillaries, and scant blood vessels. Nests of odontogenic epithelium are occasionally seen but not essential for diagnosis , 13, 23.Surgical treatment of odontogenic myxoma is usually invasive, and it depends on the size of the tumor from conservative, e.g., enucleation and surgical curettage, to radical treatment like partial or segmental jaw resection with free flaps. Smaller lesions can be treated only by curettage, but larger lesions need resection due to their infiltration to the surrounding bone. Large maxillary and mandibular bone defects can be reconstructed by fibular and iliac-crest osteomyocutaneous or osteomuscular free flaps . Free flLack of its encapsulation and loose of myxoid composition is the main reason of recurrence, so the method of removal is a crucial determinant . AccordiThe reconstruction of the mandible after radical treatment can be made by fixed or removable prostheses retained by a system attached to the implant. In some cases with reconstructed mandible with free flaps, there might be a problem due to inadequate mechanical retention during mastication so an implant-supported fixed dental prosthesis is the best solution for treatment . Meloni Implant-prosthodontic rehabilitation after marginal resection of the mandible requires filling the edentulous space and compensating the loss of hard and soft tissues, therefore presenting a particular challenge to prosthodontists. Removable dental prosthesis is preferred to an implant-supported fixed dental prosthesis to maintain oral hygiene and recurrent examinations and for long-term maintenance . Elsyad Quality of life in patients after radical surgical treatment of odontogenic myxomas is often compromised by loosing function and aesthetic morbidity. A multidisciplinary approach is the basis for complete implanto-prosthodontic rehabilitation of patients after resective surgical oncology.


Cellular senescence is a homeostatic biological process characterized by a permanent state of cell cycle arrest that can contribute to the decline of the regenerative potential and function of tissues. The increased presence of senescent cells in different neurodegenerative diseases suggests the contribution of senescence in the pathophysiology of these disorders. Although several factors can induce senescence, DNA damage, oxidative stress, neuroinflammation, and altered proteostasis have been shown to play a role in its onset. Oxidative stress contributes to accelerated aging and cognitive dysfunction stages affecting neurogenesis, neuronal differentiation, connectivity, and survival. During later life stages, it is implicated in the progression of cognitive decline, synapse loss, and neuronal degeneration. Also, neuroinflammation exacerbates oxidative stress, synaptic dysfunction, and neuronal death through the harmful effects of pro-inflammatory cytokines on cell proliferation and maturation. Both oxidative stress and neuroinflammation can induce DNA damage and alterations in DNA repair that, in turn, can exacerbate them. Another important feature associated with senescence is altered proteostasis. Because of the disruption in the function and balance of the proteome, senescence can modify the proper synthesis, folding, quality control, and degradation rate of proteins producing, in some diseases, misfolded proteins or aggregation of abnormal proteins. There is an extensive body of literature that associates cellular senescence with several neurodegenerative disorders including Alzheimer’s disease (AD), Down syndrome (DS), and Parkinson’s disease (PD). This review summarizes the evidence of the shared neuropathological events in these neurodegenerative diseases and the implication of cellular senescence in their onset or aggravation. Understanding the role that cellular senescence plays in them could help to develop new therapeutic strategies. Cellular senescence, a homeostatic process that reduces proliferation and helps to prevent the propagation of damaged cells , and mitochondrial dysfunction-associated senescence, among others  can become senescent, including astrocytes  Senescence-associated secretory phenotype (SASP), which consists of the synthesis and release of proinflammatory chemokines, cytokines, growth factors and metalloproteinases  During aging and in neurodegenerative diseases, microglial cells display altered morphology characteristic of senescence  High levels of oxidative stress have been demonstrated to induce cellular senescence during aging , and its endogenous antioxidant pathways are essential to maintain physiological redox signaling Brand, . FurtherFinally, mitochondrial ROS can also induce telomere attrition, and dysfunction  DNA damage that alters chromatin structure and activates the DNA damage response (DDR)  During replicative senescence, telomeres, DNA–proteins that protect chromosome ends from degradation, and inappropriate recombinations or fusions shorten with every cell division , histone variants, altered nucleosomal composition, alterations in DNA methylation pattern, alterations in nuclear lamina-chromatin interactions and on 3D genome organization that contributes to cellular dysfunction  Epigenetic modification such as histone modifications and specific DNA methylation changes, including alterations in the activity of methylation enzymes  Altered proteostasis. Senescence cells display increased unfolded protein response (UPR) associated with endoplasmic reticulum (ER) stress, which participates in the increase in ER size and the changes in the shape and size of these cells  autophagy andlysosomal anomalies and alterations in UPR indicative of ER stress. Correct proteostasis reduces the secretion of inflammatory cytokines  The promotion of oxidative stress and mitochondrialdysfunction. There is a positive feedback mechanism between senescence, oxidative stress, and mitochondrial dysfunction  The reduction of the regenerative capacities of the nervoussystem: adult neurogenesis has been demonstrated in rodents  Loss of function: finally, cell-cycle arrest and other alterations associated with cellular senescence alter the function of neurons and different CNS cell types  Aging increases the number of senescent cells  of hyperphosphorylated tau proteins, and loss of neurons and synapses  trigger or are associated with cellular senescence, has led to the suggestion that this process has a crucial role in the etiopathology of AD.The brains of AD patients and of mouse models of AD have higher levels of inflammation due to microglia activation that produces pro-inflammatory cytokines and other SASP mediators  and found cellular changes identical to those found in other types of senescence: i.e., an increase in SA-β-gal expression, cell cycle arrest and alterations in cellular morphology  , are essential for maintaining proteostasis , Aβ expression and tau phosphorylation, as well as increased density of senescent cells in different hippocampal regions  gene is triplicated, leading to the overexpression of the Usp16 enzyme that controls the ubiquitination state of the histone 2A (Ub-H2A) and contributes to regulate the DDR chromatin remodeling and cell cycle progression  , contributing to neurodegeneration .Senescent cells accumulate with aging and in neurodegenerative pathologies, and there is extensive evidence that they might be implicated in the etiopathology of these diseases. Here, we reviewed the data that demonstrate that cellular senescence is a common pathological feature of PD, AD, and DS. These three diseases also share some of the mechanisms that promote senescence and that allow this permanent state of cell arrest to induce or aggravate neurodegeneration. Furthermore, extensive senescence has also been found in other neurodegenerative diseases such as Huntington Disease, Multiple Sclerosis, and Rett syndrome. Thus, senescence seems to be a common mechanism for neurodegeneration that needs to be further investigated.At present, there are no efficient neuroprotective treatments that can prevent or delay the progression of the disease for AD in individuals with or without DS or for PD. Thus, new neuroprotective therapeutic approaches are needed.Because of the central role of cellular senescence in the etiopathology of different neurodegenerative diseases, therapies that reduce senescence could be a promising approach to prevent the loss of cells and the alteration of their function. These therapies have been more extensively investigated in the case of AD , are also a result of senescence, therefore aggravating the disease . Thus, tCM-C and NR wrote and edited the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Ocular surgery is one of the most performed medical procedures in the world. Its limitation or suspension, recursively extended over time, could be associated with a significant increase in the number of blind people worldwide. Indeed, cataract causes more than half of all cases of visual impairment in those countries with limited availability of means for performing eye operations . In this scenario, the pandemic of coronavirus disease 2019 (COVID-19) quickly resulted in the suspension or sharp reduction of various ophthalmic activities considered non-urgent, including lens replacement surgery or some intraocular injections. Despite the imperative need to continuously practice eye operations to avoid the abovementioned problems, there are currently little-shared and vague recommendations among the various countries on safety in operating rooms  and poor legal protection for surgeons . Herein, we individuated and discussed some critical points in safety recommendations and medical liability. A paradigm shift for ocular surgery during the COVID-19 era is now mandatory. While telemedicine has been able to solve some problems in clinical ophthalmology, the lack of adequate health and legal protection for surgeons and patients may result in an excessive reduction in the volume of surgical interventions during a pandemic era and the immediately following period, thus determining inability to ensure health care to all patients. Eye surgery is among the most performed therapeutic procedures in the world for its efficacy, safety, and demand  . With thSpecifically, cataract causes more than half of all cases of visual impairment in those countries with limited availability of means for performing eye surgery . In fact, cataract surgery is one of the most common medical interventions in Western countries where all the necessary devices are available. The prolonged suspension of this effective treatment would determine a drastic increase in the number of cases of blindness both in the Western world and in the least developed or developing countries.In this scenario, the pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) appeared unexpectedly and abruptly in December 2019 in Wuhan. Shortly, this infectious disorder represented a global health problem of great impact on the lifestyle of various populations  ,4.Despite the imperative need to continuously practice eye surgery to avoid the abovementioned problems, there are currently little-shared and vague recommendations among the various countries on safety in operating rooms for health care workers (HCWs) and patients, as well as poor legal protection for surgeons .Clearly, different considerations must be made according to the type of surgery, i.e., elective or urgent.The American Academy of Ophthalmology (AAO), i.e., the world’s largest association of eye physicians and surgeons, recommended on 18 March 2020 that all ophthalmologists stop immediately any treatment other than urgent or emergent care, thus including both office-based care and surgical care . This isThereafter, some facilities have begun to prepare for the resumption of elective surgeries based on the 16 April guidelines from the federal government , invitinIn other parts of the world with different socioeconomic needs and contexts , the reference scientific societies and scholars advised similar protective behaviors ,10,11.Of note, the British Oculoplastic Surgery Society (BOSS) highlighted a whole series of ocular surgical procedures associated with the generation of bioaerosol , in particular the lacrimal procedures. Of course, other surgeries involving the nasal or sinus cavities, open suctioning, and orbital surgery using power/electrical instruments should also require special attention .Curiously, the Royal College of Ophthalmology recommended a reduction of the length of the surgical procedures by indicating only the most experienced and older surgeons as potential operators (who are at increased risk for serious age-related complications from COVID-19), thus excluding younger surgeons from the operating room (with possible repercussions on their training courses) . ClearlyOverall, the suggested PPE for eye surgery may obviously cause a number of changes and technical difficulties for surgeons. As a result, there may be greater complexity in focusing due to goggles (with the impossibility of using a face shield), a larger and more uncomfortable distance between the operator and microscope, a different sensitivity to the foot pedal due to overshoes, and discomfort and/or skin irritation due to facial masks. Clearly, double disposable sterile surgical gloves, suggested for some surgical procedures, can also change the sensitivity of the surgeon .With this respect, the use of three-dimensional (3-D) heads-up display systems for both anterior segment and vitreoretinal surgery ,15 may hClearly, the preventive measures taken for the various types of surgical procedure imply different scenarios. As regards the impact of surgery on eye health, in case of a prolonged duration of the pandemic, the continuous postponement of elective surgery inevitably facilitates a progressive deterioration of visual function in general population.On the other hand, in urgent or emergency surgical procedures, since the onset of the pandemic, eye surgeons have quickly encountered the dilemma of how to protect patients and themselves from potential infections , and how to legally shield themselves against potential sue. These situations of risk of contagion, and the doubtful indication of when to operate or not to operate, have created many difficulties during the COVID-19 era, e.g., the complex risk/benefit assessment of each surgical procedure. In addition, there is currently also an enigma for surgeons to be faced with an asymptomatic/pre-symptomatic or with a false negative (COVID-19 tests) patient.From a theoretical point of view, it would be desirable to identify effective protocols in preventing COVID-19, with specific guidelines for each surgical specialty. In Ophthalmology, for instance, pre-surgical conjunctival and nasopharyngeal tests (swabs) may help in screening cases requiring special attention in addition to pre-surgical and post-surgical drug prophylaxis. Although there is no confirmed effective agent for post-exposure prophylaxis, as stated by the National Institutes of Health “Coronavirus 2019 (COVID-19) Treatment Guidelines” (updated 4/21/2020) , it may In any case, a responsible utilization of all personal protective equipment available for surgeons and patients, and sanitization of rooms are the best prophylactic tools available today.Among the various problems related to the COVID-19 pandemic, there are ocular surgeons’ concerns regarding the potential medical liability of the care due to scarce scientific evidences on the adequate sanitization of operating room during procedures, or related to general protection for patients.Similar concerns have been previously discussed by policy makers regarding the limited availability of means to appropriately treat patients in different contexts .Thus, some institutional organizations in the world have provided different levels of medical liability protection, though the latter was rather limited. Accordingly in the USA, for example, Congress under the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) offered legal protection to volunteer HCWs during the ongoing pandemic , while sOn the other hand, no specific protective provisions have been granted to HCWs in many other Countries around the world to protect them from potential medical liability.For example, in Italy, although there is a law proposal aimed at limiting penal liability, ordinary law is currently in force yet. To note, despite healthcare facilities are the places where infectious occur most frequently, the current law on the crime of “negligent epidemic”  does not provide for exceptions or mitigations for HCWs, potentially implying different scenarios for an act or omission , and theClearly, medical needs and scientific knowledge are changing rapidly with regards to the SARS-CoV-2 epidemic, the related treatments and tests, as well as the responses of policy makers, thus leading to ongoing variations in interim recommendations from scientific societies. Although it is not possible to entirely eliminate the risk of infection (thus obtaining the desirable zero rate) during the ongoing pandemic, prudent adjustments to the indicated precautions may be warranted ,23.Overall, guidelines adapted in this pandemic era may help protect clinical ophthalmologists and eye surgeons should anyone question the therapy decisions made during the ongoing pandemic. But as always in a medical context, guidelines represent only a flexible tool to address a clinical issue on the best available evidences, needing always a personalized implementation on the basis of personal, structural, and organizational skills and knowledge.While telemedicine has been able to solve some problems in clinical ophthalmology, the lack of adequate and precise scientific/legal indications for surgeons and patients could result in an excessive reduction in the volume of surgical interventions during a pandemic era and in the immediately following period. Additionally, the weakness and slowness of the health system may lead to the inadmissible inability to meet real needs and ensure health care to all patients.Now, the need to clarify as soon as possible the abovementioned points is therefore imperative. Otherwise, COVID-19 could remain a dilemma for eye surgeons until the discovery of effective and safe protocols for prevention and therapy, reliable point-of-care testing, and validated methods for sanitizing the operating room.


Exosomes are vesicles with a diameter of 30-150 nm produced by living cells and secreted into the extracellular matrix. Exosomes mediate cellular communication by carrying active molecules, such as nucleic acids, proteins, and liposomes. Although exosomes are found in various body fluids, little is known about bile-derived exosomes. This review is the first to summarize the methods of bile storage and isolation of biliary exosomes, highlighting the roles of bile-derived exosomes, especially exosomal noncoding RNAs, in physiological and disease states and discussing their potential clinical applications. Exosomes are vesicles secreted into the extracellular environment by the fusion of specific endosomes, i.e., multivesicular bodies (MVBs), with the plasma membrane; exosomes mediate cell-to-cell communication during many biological processes, including tumour progression and immune response , 2. ExosIn the 1990s, Johnstone et al. identified a membranous vesicle in the supernatant of in vitro culture medium of sheep erythrocytes and named it an exosome , 7. ExosBile samples are obtained at ERCP or at the time of percutaneous manipulation of biliary tubes by interventional radiology (IR). Then, the samples are placed into a sterile collection tube. In previous studies, bile was always extracted without contrast injection to ensure exosome yield and to reduce the interference of irrelevant factors –19. CellDue to the lack of current exosome extraction standards, the process varies depending on body fluids . For exaThis approach has some limitations. Ultracentrifugation requires relatively specific equipment, and the process is operationally complex and requires professional training. Limited capacity of the centrifuge rotors enables processing of only a small number of samples at one time. However, the exosomes obtained by this continuous centrifugation and filtration method are undoubtedly of high purity.http://www.hansabiomed.eu/) and Life Technologies (http://www.lifetechnologies.com/exosomes) offer an array of products featuring antibodies against CD63, CD81, and CD9 for exosome capture and characterization. Bioo Scientific introduced a kit called ExoMir that uses several microfilters to filter out cellular debris based on the size of the exosomes, and exosomes larger than 30 nm in diameter are captured. The limitation of this method is the inability to purify exosomes because other substances with a similar diameter are also present in body fluids.Certain kits, such as ExoQuick (produced by System Biosciences), separate poorly soluble exosomes from the solution by precipitation and enable their collection by low-speed centrifugation or filtration. HansaBioMed  due to their structural characteristics, i.e., 30-150 nm spherical structures, and the diameter of the exosomes in the images corresponds to exosomal characteristics, thus enabling their preliminarily identification . AdditioA previous study confirmed that biliary exosomes attached to the primary cilia in the bile duct cause a decrease in the ratio of phosphorylated ERK1/2 to total ERK1/2, an increase in the expression of miR-15A, and a decrease in the proliferation of bile duct cells  Figure ; the stuMost studies focused on the cargoes carried by the exosomes and specifically concentrated on noncoding RNAs. We have reviewed recent publications on the mechanism of exosome delivery in all types of humoral sources, and the findings are presented in detail in Similar to circulating noncoding RNA, the function of the whole system becomes complex due to the external structure of the exosomes and other substances present in the exosomes, such as DNA and proteins. For example, does the structure of external vesicles enhance their targeting ability? Is there any protection against the degradation of internal noncoding RNA? Interestingly, tetraspanins on the exosome surface have been reported to play an important role in the targeting of exosomes –39. ThisBecause of the diversity of exosome components, the effects of noncoding RNAs may be mediated by internal proteins, lipids, or DNA; the complexity of the whole process suggests that noncoding RNAs originating from exosomes may interfere with or promote any part of the process. Thus, studies of the mechanisms of action of biliary exosomes require reasonable extrapolation based on the exosomes characterized in other sources and complete description of the related biological processes, including secretion, transport, and uptake of the exosomes, and functions that are influenced by considerable heterogeneity of the exosomes , 50. StuBile is the most directly accessible internal environment for bile duct-related diseases. There is no doubt that all types of cytokines and extracellular vesicles may be enriched in bile regardless of bile duct-related tumours or inflammation levels, providing a theoretical basis for the studies of biomarkers. The presence of exosomes in bile has been confirmed, and these exosomes contain abundant microRNA species that are stable in bile. Thus, a diagnostic panel was developed based on bile duct carcinoma-associated microRNAs. The ROC curve confirmed a panel sensitivity of 67% and a specificity of 96% . InteresA number of recent studies have verified potential applications of the exosomes from various sources as biomarkers . AnalysiHowever, these conclusions cannot be blindly generalized or extended. A recent study on the diagnosis of pancreatic ductal adenocarcinoma (PDAC) confirmed that a higher frequency of mutant KRAS was detected in the circulating exosome-derived DNA in PDAC patients and in the vast majority of healthy subjects . This reExosomes are membranous vesicles with a diameter of 30-150 nm secreted by cells. Exosomes play important roles in cell-to-cell communication through the biological processes involved in their generation and secretion and targeting of receptor cells , 54. The3+) and tannic acid. Additionally, nanofilms enable the retention of the inherent size and chemical composition of the exosomes thereby promoting the controlled release of drugs [Exosomes with certain characteristics can be ideal therapeutic tools. However, certain limitations have been demonstrated. For example, it is difficult to track the exosome transport process and distribution in vivo. Fortunately, some researchers have developed a means of direct labelling of the exosomes through gas-coated gold nanoparticles (GNPs) and identified the distribution of these exosomes using computed tomography to determine the best drug delivery routes . Anotherof drugs . The cliof drugs . The appThe c(RGDyK) peptide was conjugated to the exosomes in a certain manner, and these exosomes were used as carriers to deliver curcumin in a targeted manner in an ischaemic stroke model in mice; this treatment produced anti-inflammatory effects in the brain and overcame the inability of drugs to pass the blood-brain barrier . SimilarBile is a special fluid secreted by the liver and transported through the bile ducts. Bile does not reach the whole body; therefore, characteristics of bile can be used to accurately diagnose diseases of the biliary tract. There is no doubt that biliary exosomes may have possible therapeutic uses and effects based on principles described in the present review. Bile is the most directly accessible contact environment in the diseases of the bile duct system; thus, bile-specific exosomes may produce better therapeutic effects. For example, circ-CCAC1 in biliary exosomes may play an important role in CCA progression; therefore, suppression of circ-CCAC1 expression or blocking the transmission of exosomal circ-CCAC1 might be a novel therapeutic strategy for CCA . FurtherIn brief, we reviewed the biogenesis and development of exosomes, provided the initial theoretical basis for future mechanistic studies, summarized the isolation and identification of biliary exosomes for the first time, and highlighted the mechanisms and principles of the effects of exosomes in bile and the clinical application potential of the exosomes . We desc


Although the advent of enzyme replacement therapy (ERT) for mucopolysaccharidoses (MPS) has paved the way for the treatment for these hereditary disorders, the blood brain barrier (BBB) has prevented patients with MPS involving the central nervous system (CNS) from benefitting from ERT. Therefore, finding ways to increase drug delivery into the brain across the BBB remains a crucial challenge for researchers and clinicians in the field. Attempts have been made to boost brain uptake of enzymes by targeting various receptors , and several other administration routes have also been tested. This review summarizes the available information on clinical trials  of novel therapeutic agents with efficacy against CNS symptoms in neuropathic MPS and also discusses the common associated challenges and pitfalls, some of which may help elucidate the pathogenesis of the neurodegeneration leading to the manifold CNS symptoms. A summary of current knowledge pertaining to the neuropathological progression and resultant neuropsychiatric manifestations is also provided, because it should be useful to ERT researchers looking for better approaches to treating CNS lesions in MPS. The advent of enzyme replacement therapy (ERT) for lysosomal storage disorders, spearheaded in 1991 by the introduction of glucocerebrosidase for Gaucher disease and followed in 2003 by that of laronidase (α-iduronidase) for mucopolysaccharidoses (MPS) type I [Efforts have been made to boost brain uptake of drugs across the BBB by targeting various receptors  located on the vascular endothelial cells where, by way of transcytosis, modified enzymes are delivered into and exert effects on the brain. Positive results have been reported in preclinical and clinical studies on MPS-I  and MPS-Research carried out to develop novel therapeutics for neuropathic MPS can shed light on the nature of progressive neurodegeneration itself: although the basic etiology is clearly demarcated as a genetic deficiency in an enzyme that results in substrate accumulation, the progression of degeneration and the pathogenesis of the resultant manifold CNS symptoms are still in need of further elucidation, which is likely to come from research aimed at developing novel ERTs for neurodegeneration. For this reason, this paper also includes a brief summary of reported neuropathological findings and corresponding neuropsychiatric manifestations, with some suggestions on possible ways forward to better understand and address neuropathic MPS.Treatments for MPS are out of necessity multidisciplinary because of the multi-systemic nature of the disease. They can be divided into two major categories, general and specific ,9. GenerGeneral treatments include symptomatic management of neuropsychiatric symptoms  with psychotropic agents, mood stabilizers, and anticonvulsants ,11. SurgThe specific treatments currently available for MPS, apart from ERT, include hematopoietic stem cell transplantation, substrate reduction therapy, chaperon therapy, and gene therapy. These are covered elsewhere in this Special Issue, so this paper focuses on an ERT for neuropathic MPS.The goal of ERT is to compensate for genetic enzyme deficiency by regularly administering recombinant enzymes, thereby preventing, improving, stabilizing, or decelerating the various systemic symptoms generated by accumulated substrates and the associated pathophysiology. At the time of writing, four recombinant enzymes have been approved for the treatment of MPS in most industrialized nations: laronidase for MPS I, idursulfase for MPS II, galsulfase for MPS VI, and vestronidase for MPS VII. No recombinant enzyme products have yet been developed to treat the three other types of MPS. For types I, II, III, and VII, even the currently available enzymes can only address the systemic symptoms, leaving neurodegeneration to progress unhindered. As detailed later, progressive neurodegeneration and its clinical manifestations constitute the most pressing challenge, both scientifically and clinically, in developing treatments for MPS. Besides, it is also worth noting that the currently available ERTs have only limited efficacy in treating skeletal, respiratory, and eye lesions . RegardiThese limitations point to the need for further elucidation of neurodegeneration and the subsequent pathogenesis of CNS manifestations on the one hand and for concentrated and multidisciplinary efforts to develop novel therapeutics for neuropathic MPS on the other . TherefoDeficiencies in lysosomal enzymes in neuropathic MPS lead to excessive intra- and extra-cellular substance (glucosaminoglycan (GAG)) accumulations, causing widespread tissue and organ dysfunction and systemic structural damage. Four major GAG polysaccharides (heparan sulfate (HS), keratan sulfate (KS), dermatan sulfate (DS), and chondroitin sulfate (CS)) are known to play decisive roles in the pathogenesis of MPS ,16. A suIn contrast to the clear causal relationship between enzyme deficiency and resultant GAG accumulation, the pathogenic processes leading from GAG accumulation to clinical manifestations are complex and multifaceted ,19,20,21First, GAG accumulation in neurons brings about cellular changes by way of primary  and secondary  accumulations, which eventually give rise to gross neuroanatomical changes across various regions in the brain. Additionally, in some types of MPS, e.g., IIB, secondary accumulations of gangliosides contribute further to this process . ProbablUnlike other neurodegenerative disorders in which lesion localization is specific to each disease  Enzyme modulation: Enzymes are fused with antibodies for the receptors on the capillary endothelial cells of the brain, allowing endocytosis through the receptors into the endothelial cells, followed by exocytosis into the abluminal space in the brain; this method helps deliver enzymes from the blood within the vascular lumen into the brain parenchyma.(2) Modified routes of administration: Intrathecal ,7, intra(3) Dose escalation to increase drug delivery through the BBB: enzymal products are administered at high dosages to maximize the intracerebral concentration and compensate for the loss of some of the administered drug when it is blocked by the BBB.This paper focuses on the first strategy, enzyme modulation.Despite the BBB’s role in blocking external substances from penetrating into the brain parenchyma, some endogenous proteins  cross the BBB through specific receptors expressed on the luminal side of brain capillary endothelial cells ,35,36. TThe putative mechanism of action of transcytosis, by which the delivery of the fusion protein into the brain is achieved, is as follows . First, Monkey and mouse models of MPS-II have respectively provided preclinical evidence of the delivery of enzymes into the brain by transcytosis via insulin receptors  and tranThere are several notable challenges in the development of novel ERTs for neuropathic MPS. One concerns the issue of the delivery of enzymes across the BBB, as discussed in (1) Clinicopathological heterogeneity of the patient population:While neuropathic MPS itself has a fairly homogeneous genetic background, patients with the disease show immense phenotypic heterogeneity in terms of disease progression and severity of clinical CNS manifestations ; this he(2) Definition of endpoints and their evaluation:CNS manifestations, as summarized in There is no knowing at the moment which neurological and psychiatric symptoms reflect neuronal dysfunction versus neuronal loss at which level in this hierarchy. As a result, “informed guesswork”  based onRegarding the neurodevelopmental trajectory, a precise evaluation of the neurocognitive effects of new treatments ideally requires a comparison of three different trajectories: (1) the normal neurocognitive development in very young children, (2) the natural history of neurocognitive impairment in the patients with neuropathic MPS, and 3) the observed neurodevelopmental trajectory of the MPS patients receiving a novel ERT in its clinical trial. In practice, this comparison involves a number of further issues, e.g., limited availability of the natural history data , differe the obseOne potential solution to enable successful completion of clinical trials leading to a timely regulatory approval for these rare and severe diseases on the one hand and a reasonably robust longitudinal data analysis comparing the developmental trajectories on the other would be a post-approval collection of neurocognitive data from the patients enrolled in the clinical trials. In this way, the pre- and post-approval neurocognitive datasets can be combined to maximize their values for the longitudinal efficacy evaluation of novel ERT for neurocognitive impairment even in the limited patient population with marked heterogeneity.In addition to neuropathic MPS, there are many lysosomal storage disorders (LSDs) with CNS involvement, all of which are in need of effective treatments to deal with the associated neurodegeneration. Therefore, the challenges facing researchers in the development of novel ERTs for neuropathic MPS apply equally to those seeking ways to treat other LSDs involving the CNS. To address the multi-systemic symptoms of LSDs, a new polyvalent therapeutic strategy  based onTo deal with these challenges, multidisciplinary approaches are essential. From the clinical point of view, a wide range of medical specialties needs to be involved in dealing with the variety of clinical manifestations. In particular, to better understand, evaluate, and take care of the CNS symptoms in neuropathic MPS, neurology and psychiatry, neurolinguistics, neuropsychology, and neuroimaging, among other subspecialties, are indispensable. Developing and manufacturing novel enzymes that can cross the BBB to reach the CNS will require advanced knowledge and state-of-the-art technologies from the fields of molecular genetics, immunology, and proteomics and timely responses to new guidelines and regulations applying to rare diseases . Interna


The making of a protein is based on the combination of 20 different monomers  giving the possibility of building a variety of structures from the simplest to the most complex, rigid or highly dynamic, and suited to carry out a wide range of structural and functional roles. However, proteins are required to adapt their structures to the needs of the organism and, in general, to any changes in the surrounding molecular environment, and are therefore subjected to continuous fine-tuning regulation. Post-translational modifications (PTMs) represent one of the most important mechanisms underlying this regulation. It is therefore not surprising that aberrant regulation of PTMs may be involved in different human diseases, including cancer, neurodegeneration, diabetes, and inflammatory diseases, and that the enzymes regulating their turnover are considered pharmacological targets of primary importance.Among PTMs, phosphorylation is the most well-investigated and many writers (kinases), erasers (phosphatases), and readers (phosphor-binding domains) of this PTM have been thoroughly characterized; probably almost all biological events are in some manner under the control of a phosphorylation switch. However, despite all, a full picture of the role of phosphorylation is far from being reached—just to think that, to date, more than 200,000 phosphosites  have beOur recently published Special Issue “Protein Post-translational Modifications in Signal Transduction and Diseases” includes six research articles and six review articles spanning a variety of PTMs and biological processes.Schizosaccharomyces pombe) may undergo auto-methylation and thus promoting self-activation. Furthermore, the authors proposed that Clr4 auto-methylation could act as a sensor of S-Adenosyl methionine cellular levels thus modulating heterochromatin formation according to the nutrient availability and the metabolic state of the cell [Protein methylation is a PTM that occurs at both lysine and arginine residues; this PTM has been mainly characterized in histone proteins and is associated with transcriptionally active chromatin. Khella et al. shed light on the mechanism by which Clr4  plays a pivotal role in regulating the root development in plants; in their work, Niu et al. furnish experimental evidence that NO might induce adventitious rooting in cucumber through enhancing S-nitrosylation of a large variety of proteins. Moreover, functional analysis of nitrosylated proteins suggests that carbon and energy metabolism processes can be regulated by S-nitrosylation during root development .Two papers of this special issue deal with PTMs in mitochondria. Even though PTMs in mitochondria have been often overlooked in the past, it has now been recognized that modifications of mitochondrial proteins represent a key mechanism in regulating organelle functions, including mitochondrial metabolic pathways, transport across the inner and outer membranes, fission, fusion, and degradation ,10. In tNot surprisingly, PTMs have also been identified in viral proteins. Kumar and colleagues take us on a journey into the world of the RNA virus, describing one by one all the most important PTMs identified in host and virus proteins regulating RNA virus replication .Alpha-1-antitrypsin is an anti-inflammatory glycoprotein and a serine protease inhibitor produced by the liver and released into the bloodstream. Its genetic deficiency increases the risk of developing lung and liver disease. Lechowicz and colleagues in their review summarize the PTMs identified in this protein, and their functions, showing how an extracellular protein is also variably affected and regulated by PTMs .Luiken’s group give us a detailed picture of the role of palmitoylation, a reversible modification consisting of the addition of palmitate to cysteine residues regulating protein targeting to membranes, in the insulin signaling pathways in the heart . MoreoveThe last review focuses on the role of lysine acetylation in Parkinson’s disease (PD), one of the most common neurodegenerative diseases. The authors show how acetylation of histone and non-histone proteins and the expression of the enzymes regulating their turnover (lysine acetyltransferases and deacetylases) are affected in PD patients and different PD models, discussing potential therapeutic interventions .In the future, one important aspect that should be investigated more deeply is the crosstalk between different PTMs. Indeed, the same residue may be subjected to different mutually exclusive PTMs. For instance, it could happen that the same lysine may undergo methylation, acetylation, ubiquitylation, or sumoylation, and each of these may determine a different biological outcome ,18. In a