A violent and harmful attempt to tactically manipulate the COVID-19 vaccine debate in Italy, France, and Germany. The following focal issues are discussed: (1) CIB manipulative operations, (2) their extensions, and (3) challenges in CIB's identification. The article shows that CIB acts in three domains: (i) structuring inauthentic online communities, (ii) exploiting social media technology, and (iii) deceiving algorithms to extend communication outreach to unaware social media users, a matter of concern for the general audience of CIB-illiterates. Upcoming threats, open issues, and future research directions are discussed.Coordinated inauthentic behavior (CIB) is a manipulative communication tactic that uses a mix of authentic, fake, and duplicated social media accounts to operate as an adversarial network (AN) across multiple social media platforms. The article aims to clarify how CIB's emerging communication tactic “secretly” exploits technology to massively harass, harm, or mislead the online debate around crucial issues for society, like the COVID-19 vaccination. CIB's manipulative operations could be one of the greatest threats to freedom of expression and democracy in our society. CIB campaigns mislead others by acting with pre-arranged exceptional similarity and “secret” operations. Previous theoretical frameworks failed to evaluate the role of CIB on vaccination attitudes and behavior. In light of recent international and interdisciplinary CIB research, this study critically analyzes the case of a COVID-19 anti-vaccine adversarial network removed from Meta at the end of 2021 for  This article aims to clarify how CIB's emerging communication tactic “secretly” exploits social media technology to massively harass, harm, and mislead the online debate around crucial issues for society, like the COVID-19 vaccination.Coordinated Inauthentic Behavior (CIB) is an emerging manipulative communication tactic using a mix of authentic, adversarial network's leaders is part of the CIB deception. CIB campaigns mislead others about who they are and what they are doing by acting with pre-arranged or exceptional similarities  coordination could harm democracy and society. Moreover, how CIBs are deliberately organized, resourced, and reinforced by digital platforms' algorithms and paid services is still unclear, a little-studied phenomenon in social sciences that needs further investigation.Since CIB is an emerging phenomenon, it is still unclear how it “secretly” In order to clarify these issues, this article is organized into three parts: first, traditional theoretical frameworks that may explain vaccination attitudes and behaviors are considered. Second, current interdisciplinary and international literature is reviewed according to three research questions and dimensions: (a) CIB operations , (b) expansion, and (c) identification . In this context, a critical examination emerges from analyzing a rare case of COVID-19 anti-vaccination network removed from Meta at the end of 2021. Third, open issues, current limits, and a future research agenda on CIB manipulative tactics are discussed.platforms' technology  to deceive the public communication debate.The central hypothesis that moves this study's investigation is that emerging forms of coordinated inauthentic behavior exploit operate? Do CIB manipulative operations revolve around inauthentic content or malicious agents' tactics? .(RQ1) How CIBs extend CIB's manipulative communication outreach? . How CIBs deceive social media algorithms?(RQ2) Could social media technology identifying CIB in the vast social media ecosystem? ((RQ3) What are the challenges in osystem? .Vaccine opposition, hesitancy, and acceptance Kata,  have eximanipulative role of CIB on COVID-19 vaccination attitudes and behaviors in contemporary online debates.Theoretical frameworks and constructs based on empirical observations of human argumentations emerged over time  opposing what they called “the healthcare dictatorship”  psychological harassment and (2) exploitation of technology warriors” fighting a psychological war against COVID-19 vaccination sustainers in Italy, France, Germany, and other countries. The anti-vaccine leaders coordinated actions across multiple digital platforms  to psychologically mass-harass specific targets in online and offline contexts. For example, the removed network aimed at misleading and silencing specific targets who had publicly sustained vaccination—journalists, health care providers, politicians, actors, and social media influencers.According to Gleicher et al. , the antdislike buttons (to disapprove of pro-vaccine posts), orchestrated negative comments to opponent's posts, or even requests to “suspend” specific (pro-vaccine) accounts by inauthentically and massively reporting misconduct  to tactically gain digital visibility and therefore increase algorithmic “popularity” ranking metrics  the reactions of others, such as the number of comments a post reaches, the number of likes/dislikes obtained, the type, and the number of emoji reactions and more.First, the actor or account “popularity” is a measure estimated by the platform's algorithms . Individual metrics mainly depend on two aspects (a) the extension a CIB communication campaign can reach is economic. Social media offer a range of paid advertising services that users can purchase to promote their posts for specific micro-targeting actions beyond their followers' reach. Questionably, but coherently with the social media business logic, a significant investment could enormously extend the range of communication outreach.A second aspect influencing the degree of quantified attention  algorithms could spread disinformation faster  content to the platform's users, social media algorithms can significantly advantage those interested in amplifying visibility and information outreach. However, combining paid ads or identified and removed from all its platforms. Detecting CIB manipulative operations is challenging  can influence opinion trends  operative coordination, (ii) techno-manipulation extensibility, and (iii) identification/removal.hard-to-identify CIB manipulation could be dangerous to democracy and society because of how it is deliberately organized, resourced by malicious actors, and reinforced by digital technologies. CIBs mislead others, following manipulative goals and communication tactics, and hiding the identity of their leaders.CIBs' manipulative communication could be one of the greatest threats to freedom of expression and democracy in the social media ecosystem  revealed a violent attempt to repetitively manipulate the COVID-19 vaccine debate in Italy, France, and Germany by exploiting current technology opportunities and weaknesses . Sabotage of the vaccination hubs booking system resulted in economic damage, public health challenges, and an impediment to others willing to vaccinate, particularly fragile and older people.The removal from all Meta platforms of an extensive adversarial network We should note that Meta has not (yet) authorized this author's request to access (big) data from the removed anti-vaccine adversarial network, limiting the possibility of empirically analyzing the phenomenon. To overcome this limit, in the present article, CIB dynamics were observed in different contexts to identify emerging threats to online/offline communication internationally. The manipulative influence of CIBs is rapidly growing in political debates . Also, traditional theoretical frameworks explaining online vaccination issues  should evaluate the intervening role of CIB manipulative campaigns on individual attitudes and decision-making. The measurement of the impact of CIB on individuals and society could offer crucial evidence to understand manipulative tactics and counteract them in depth.authenticity of the online debate and identifying emerging online/offline threats due to advances in sophisticated technologies like Artificial Intelligence  unregulated sophisticated technology and outreach communication goals. Safeguarding the The author confirms being the sole contributor of this work and has approved it for publication.


Coronary sinus thrombosis (CST) is a rare condition, primarily occurring after instrumentation of the heart, with no prior reported cases diagnosed via point-of-care ultrasound or of spontaneous occurrence without predisposing medical or surgical history. Patients typically present with critical illness, and CST has a reported mortality of 80%.We present a case of a healthy 38-year-old male with chest pain one hour after cocaine use, with an electrocardiogram pattern consistent with Wellens syndrome, whose point-of-care cardiac ultrasound revealed CST.This uncommon ultrasonographic finding has never been reported in the emergency medicine literature to our knowledge. It can be recognized by the clinician sonographer during standard point-of-care transthoracic echocardiogram. Coronary sinus thrombosis (CST) refers to clot formation within the blood vessel that drains most of the coronary arteries’ deoxygenated blood. This vessel travels posterior to the junction of the left atrium and left ventricle before emptying directly into the right atrium. Coronary sinus thrombosis occurs as a rare complication of intracardiac instrumentation and very rarely due to infective endocarditis, congenital structural abnormalities, myocardial infarction, or prothrombotic states, with no previously reported cases occurring without predisposing medical or surgical history or in the setting of substance use.3A 38-year-old male with a past medical history only of substance use disorder presented to the emergency department (ED) 20 minutes following intranasal stimulant use. The patient complained of severe chest pain that was sudden in onset, non-exertional, and non-radiating. He also reported mild shortness of breath and anxiety. Prehospital responders noted initial relief of his chest pain and shortness of breath following administration of 325 milligrams (mg) of aspirin and 0.4 mg of sublingual nitroglycerin, but the pain returned upon arrival to the ED. The patient’s initial vital signs at time of presentation included a blood pressure of 156/108 millimeters of mercury (mmHg), heart rate of 79 beats per minute, respiratory rate of 18 breaths per minute, and oxygen saturation of 100% on room air. Upon arrival, the patient reported chest pain and fatigue and denied any other symptoms. He also denied any family history of cardiac disease.On physical examination, the patient appeared drowsy and had symmetrically small but not pinpoint, equally round and reactive pupils. Cardiopulmonary exam and complete physical examination were unremarkable. The emergency clinician obtained an ECG, chest radiograph, troponin level, complete blood count, comprehensive metabolic panel, and a bedside transthoracic echocardiogram (TTE) to guide medical management. The initial electrocardiogram ECG  revealedA cardiology consultation was initiated, and point-of-care TTE was then performed by emergency clinicians at point of care. On parasternal long view, a circular, hyperechoic focus was noted posterior to the left atrium, at the location of the coronary sinus . This caResults from the patient’s blood tests came back unremarkable, including a normal troponin. Urine toxicology screen was positive for cocaine and opioids and negative for amphetamines. A chest radiograph was within normal limits. A comprehensive echocardiogram was subsequently performed and confirmed the diagnosis of CST. Because the patient was pain free, hemodynamically stable, and with negative serial troponins, cardiology recommended inpatient monitoring and anticoagulation, and did not recommend clot retrieval.The occurrence of CST is exceedingly rare. Most instances occur as a complication of right heart instrumentation, infective endocarditis, hypercoagulable states, or congenital malformation.What do we already know about this clinical entity?Coronary sinus thrombosis (CST) is a rare condition primarily occurring after instrumentation of the heart, with an 80% mortality rate.What makes this presentation of disease reportable?This is the first report of CST detected via point-of-care-ultrasound (POCUS) in a patient with no predisposing history but with recent cocaine use.What is the major learning point?Point-of-care-ultrasound is a valuable bedside tool that can detect rare conditions and track a dynamic pathologic process such as CST.How might this improve emergency medicine practice?Subtle abnormalities on POCUS can suggest possible uncommon pathological conditions. Combined with consultative echocardiography it can be useful in difficult cases.While cocaine is classically associated with coronary artery vasospasm and arrhythmia, its thrombogenic effects can be just as lethal.Coronary sinus thrombosis may be acute or chronic and typically presents as a severe condition, with signs and symptoms including chest pain, shortness of breath, and hypotension.To date, POCUS has not been a common diagnostic tool for CST; in fact, we were unable to identify any prior published reports of point-of-care imaging used to diagnose CST. Previously, CST has been diagnosed using comprehensive echocardiography from either a transthoracic or transesophageal approach, with transesophageal views being more sensitive. Unlike comprehensive echocardiography performed by ultrasound technologists, POCUS allows for easy serial sonographic evaluation. Our consulting cardiologist reviewed and found dynamic changes between the initial POCUS study, a comprehensive echocardiogram obtained two hours later, and a repeat POCUS performed approximately four hours after the initial one. While the first images showed complete occlusion of the coronary sinus, the comprehensive study showed a slightly smaller thrombus with some flow present around the thrombus on color Doppler. The images obtained at four hours showed an even smaller thrombus within the coronary sinus. These progressive findings over hours may have increased the likelihood of this patient’s CST being related to his reported substance use that same day.Dynamic ECG changes such as ST-segment elevations and left axis deviation can be found in acute CST, most likely due to increased myocardial perfusion pressure and decreased coronary artery blood flow leading to acute ischemia of the myocardium.There are no current guidelines for the management of CST, and treatment has varied by case given the rarity of the condition.2In a case report detailing CST as a complication of ventricular free-wall rupture following a myocardial infarction, the risk of hemorrhage into the pericardium was deemed too great, and the patient was managed without anticoagulation, ultimately doing well with conservative management.Coronary sinus thrombosis is a rare condition that has never before been reported as detected by POCUS. Classically, point-of-care TTE is used for the assessment of gross left ventricular systolic function, detection of a pericardial effusion, and evaluation for right heart strain. As clinicians become more comfortable with performing these evaluations, other subtle and less common findings will be detected. Point-of-care ultrasound is a valuable bedside assessment tool for patients with chest pain and ECG changes and can be used to track a dynamic pathologic process such as CST. As in our case, the ECG pattern, along with the detection of a hyperechoic lesion in the location of the coronary sinus, triggered specialist consultation, comprehensive TTE, and therapeutic intervention.


Editorial on the Research TopicMetabolic changes in vascular disorders: A path for early diagnosis and new therapeutic targetsAbnormal metabolic pathways have been associated with different pathological conditions, including disorders of the vascular system. Vascular disorders include atherosclerosis, hypertension, deep vein thrombosis, and pulmonary embolism, which all involve abnormalities of the vessels. This Editorial combines information from seven recent reports under the Research Topic “Metabolic Alterations in Cardiopulmonary Vascular Dysfunction” and aims to shift attention toward the targeting of metabolic alternations as a possible therapeutic approach for the management of vascular disorders and/or establishing them as new markers for early diagnosis.Vascular disorders encompass different types of pathological conditions, and so far, there have been no reports on the prevalence of all types of vascular disorders combined. However, cardiovascular disorders have been reported to be a leading cause of death worldwide, affecting approximately 523 million people  and accoThe targeting of metabolic pathways has emerged as a possible therapeutic strategy for cancer management . ConsideLiu et al. pulmonary hypertension presents with hyperproliferative vascular cells and shares a similar metabolic pathway with cancer in terms of activated aerobic glycolysis promoting cellular proliferation. Two other altered metabolic pathways are also reported, including glutamine metabolism and the Randle cycle. The authors encourage further evaluation of these pathways as possible therapeutic targets for the management of pulmonary hypertension as the currently available drugs do not halt disease progression nor do they reverse pulmonary vascular remodeling .In a review by By performing targeted metabolomics and multi-omics in rat models of pulmonary hypertension-induced right ventricular failure (PH-RVF), several common metabolites from key pathways, such as glycolysis, fatty acid metabolism, oxidative phosphorylation, and the tricarboxylic acid (TCA) cycle, were found to be significantly altered, highlighting the importance of considering these as targets for PH-RVF treatment .Liu et al. it was reported that vascular calcification, a hallmark of cardiovascular disease, is attributed to altered metabolic pathways contributing to mitochondrial dysfunction. This in turn can promote oxidative stress and alter calcium homeostasis. Thus, based on the compelling evidence of the role of abnormal mitochondrial metabolic pathways in vascular calcification, it is important to consider this organelle and its metabolic pathways as a therapeutic target for vascular calcification .In another review by Al-Abcha et al.). Considering the importance of the genetic testing guided therapy, promoting their implementation among the health care systems is highly encouraged, especially with narrow therapeutic window drugs.Genetic variations can also contribute to alterations in the metabolic pathways, and the response to drugs can be different among individuals. One review highlighted the importance of the genotype-guided use of purinergic receptor type Y subtype 12 (P2Y12) inhibitors as an anti-platelet therapy for preventing bleeding and thrombotic complications .Studying the causative factors for threatening illnesses is also important for targeting and managing these factors to prevent them from contributing to more serious conditions. A study that used two-sample Mendelian randomization (TSMR) analysis from the available genome-wide association studies (GWASs) has found that blood pressure (BP) is a strong causal effect of myocardial infarction (MI) and there is no causal effect of MI on BP, thus recommending the optimization of BP control to prevent MI, and suggesting that hypertension medications can be used to effectively prevent MI (OGDHL) gene, which is a metabolism-related gene, is upregulated in DCM patients along with a higher OGDHL protein level; thus, it can be considered as a potential biomarker for myocardial remodeling in DCM . Also, D-dimer, which is a product of fibrin degradation, along with electrocardiogram (ECG) abnormality, have been found to be significantly associated with illness severity and death in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), probably related to SARS-CoV-2-induced thrombosis; thus, they can be employed as biomarkers for predicting disease severity, and patients with higher D-dimer levels can be monitored early with more care provided throughout their illness .Lastly, it is also important to consider these metabolic changes as possible biomarkers for early diagnosis to halt disease progression. One study analyzed gene expression data from the Gene Expression Omnibus database and identified six metabolism-related genes as potential key players in the development of dilated cardiomyopathy (DCM). They reported that the oxoglutarate dehydrogenase L (This collection gathers information from compelling reports on the role of metabolic abnormalities in vascular disorders, highlighting the importance of considering them as possible therapeutic targets and early diagnostic markers for the management of the different pathological conditions associated with vascular abnormalities.


The leading cause of worldwide mortality is cardiovascular disease (CVD) . DespiteLiu et al. discuss how they established a model for coronary microembolization (CME) in rats, and report that ferroptosis and inflammation are two key players in CME-induced myocardial injury. The authors then show that suppressing ferroptosis attenuates myocardial injury and inflammation following CME. It appears that Ptgs2, a core factor in ferroptosis, and Hif1a are the two mediators of this suppressed ferroptosis. Importantly, the authors further report that by inhibiting the Hif1a/Ptgs2 axis, atorvastatin was able to suppress ferroptosis-dependent CME-precipitated myocardial injury and inflammation .Myocardial injury continues to be a major contributor to CVD-associated mortality. In this thematic issue, Cassano et al. report that in patients suffering from heart failure with reduced ejection fraction (HFrEF), sacubitril/valsartan suppressed oxidative stress, inhibited platelet activation, and improved endothelial dysfunction. These findings further support the utilization of sacubitril/valsartan in HFrEF, especially that the beneficial effects reported were noticed after 6 months of having patients on sacubitril/valsartan.In a longitudinal study, Fang et al. show that mitochondrial fission is an emerging player in vascular smooth muscle cell lipid deposition and foaming. The authors also report that stimulation with oxidized low-density lipoprotein (ox-LDL) could drive over-fission, and eventually precipitating dysfunction, of mitochondria . Interestingly, some natural products are being considered as agents that could reduce the burden of mitochondrial dysfunction. In this Research Topic, Liao et al. discuss how natural compounds could target mitochondrial dysfunction, and how such an approach could be an emerging tactic to treat or ameliorate organ damage in hypertension . Among these natural compounds are flavonoids and alkaloids, which are known to exert various cardio-vasculoprotective roles  during the postnatal period of the rat. Importantly, this remodeling is also reflected in the functional responsiveness of these very arteries where the endothelium-dependent hyperpolarization component of dilation is shown to develop postnatally  and that dilation occurs in a mechanism that appears to mirror the structural maturation of the internal elastic lamina .Morgaan et al. investigated the impact of pre-eclampsia on the renal and hemodynamic disturbances in endotoxic adult offspring, and whether these perturbations can be ameliorated with the antenatal administration of pioglitazone with or without losartan. Interestingly, this study highlights a role for the sex of the animal in pre-eclamptic fetal programming of hemodynamic and renovascular effects of endotoxemia in the adult offspring of the rat . Moreover, prenatal pioglitazone/losartan therapy appears to be superior to individual therapy in suppressing the inflammatory response in pre-eclamptic rats .Papers presented in the Research Topic cover a variety of emerging mechanisms for CVD progression. Further research on such mechanisms will pave road for better therapies. Maybe more importantly, several of the papers involved pre-clinical pharmaceutical approaches to suppress investigated cardiac injuries. Knowledge from these works will be critically important for following clinical studies.


The primary goal of radiotherapy (RT) is to induce cellular damage on malignant cells; however, it is becoming increasingly recognized the important role played by the tumor microenvironment (TME) in therapy outcomes. Therapeutic irradiation of tumor lesions provokes profound cellular and biological reconfigurations within the TME that ultimately may influence the fate of the therapy.Cancer-associated fibroblasts (CAFs) are known to participate in all stages of cancer progression and are increasingly acknowledged to contribute to therapy resistance. Accumulated evidence suggests that, upon radiation, fibroblasts/CAFs avoid cell death but instead enter a permanent senescent state, which in turn may influence the behavior of tumor cells and other components of the TME. Despite the proposed participation of senescent fibroblasts on tumor radioprotection, it is still incompletely understood the impact that RT has on CAFs and the ultimate role that irradiated CAFs have on therapy outcomes. Some of the current controversies may emerge from generalizing observations obtained using normal fibroblasts and CAFs, which are different cell entities that may respond differently to radiation exposure.In this review we present current knowledge on the field of CAFs role in radiotherapy; we discuss the potential tumorigenic functions of radiation-induced senescent fibroblasts and CAFs and we make an effort to integrate the knowledge emerging from preclinical experimentation with observations from the clinics.Video AbstractThe online version contains supplementary material available at 10.1186/s12964-023-01093-5. Radiotherapy (RT) is currently used to treat more than 50% of all diagnosed cancer cases and counts for around 40% of all cure rates. The primary goal of RT has always been to induce damage on tumor cells; thus, it has been traditionally believed that the therapeutic efficacy of RT is mediated exclusively by its capacity to directly kill malignant cells. However, tumors are complex tissues composed of multiple cellular and acellular elements often referred as the tumor microenvironment (TME) or tumor stroma. Both, the malignant and the non-malignant cells in tumors receive the same prescribed radiation dose during treatment. In recent years, it has become more and more evident the fundamental role played by elements of the TME on therapy outcomes. One of the most abundant and influential elements of the reactive stroma in tumors are cancer-associated fibroblasts (CAFs). CAFs are also exposed to the full prescribed radiation dose during the course of radiotherapy. Accumulated evidence suggests that, upon radiation, fibroblasts/CAFs avoid cell death but instead enter a permanent senescent (growth arrest) state, which in turn may influence the behavior of tumor cells and other components of the TME. Despite the proposed participation of senescent fibroblasts on tumor radioprotection, it is still incompletely understood the impact that RT has on CAFs and the ultimate role that irradiated CAFs have on therapy outcomes. Further research using appropriate experimental models to study CAFs, and more information from clinical research is needed to unveil the ultimate role played by CAFs on radiotherapy.The online version contains supplementary material available at 10.1186/s12964-023-01093-5. Radiotherapy is currently used to treat more than 50% of all diagnosed cancer cases and counts for around 40% of all cure rates . TraditiAs one of the most abundant elements of the reactive stroma in solid tumors, cancer-associated fibroblasts (CAFs) –20 are eFibroblasts are spindle-shaped cells of mesenchymal origin which reside in connective tissues and are responsible for the production of ECM components and connective tissue homeostasis . The embActivation of tissue resident fibroblasts can occur in physiological conditions, such as wound healing or acute organ repair, or in pathologic conditions such as chronic infections, organ fibrosis, autoimmune diseases, or cancer , 45. ActWith the advent of single-cell sequencing, the complexity of CAF biology during tumor development and across different tumor entities has gradually become more evident , 51, 52.Cellular senescence is an established tumor suppressive mechanism that halts the proliferation of premalignant cells . ReplicaIn the context of cancer, senescent cells can act as a double-edged sword. On one hand, SASP promotes tissue repair through the induction of plasticity and stemness and participates in the clearance of cancer and damaged cells by attracting phagocytes, NK cells and other immune cells , 62. IndSenescence-associated alterations in the secretion of matricellular proteins and ECM constituents by fibroblasts have been shown to create a favorable milieu for tumor development . The obsIonizing radiation has been shown to drive both stromal fibroblasts and cancer cells to premature senescence , 74, 75.In the context of radiotherapy, accumulated evidence reveals that on one hand, radiation-induced premature senescence instead of apoptosis is a major mode of cell fate in irradiated fibroblasts, and on the other hand, radiation-induced senescence is a dose-dependent factor, with higher doses being more effective in inducing premature senescence , 28. ExpCollectively, the accumulated knowledge clearly indicate that radiation of normal tissue fibroblasts may turn them pro-tumorigenic via acquisition of a senescent phenotype and the associated pro-tumorigenic SASP. Also, the accumulation of senescent fibroblasts in premalignant tissues by processes of normal aging or genotoxic stress (radiation) may create a favorable environment for tumor initiation and growth Table .Aiming at understanding the contribution of CAFs in tumor radio-resistance, some groups have investigated the potential radioprotective effects exerted by CAFs (non-irradiated/non-senescent) on cancer cells Table . SeveralIn clinical settings, the enhanced expression of CAF-specific markers or CAF-related gene signatures in tumor specimens have shown potential to predict responses to radio(chemo)therapy, and is persistently associated with poor prognosis in different types of cancers, including prostate cancer , cervicaIn addition to the general radioprotective functions assigned to CAFs, some studies claim that radiation exposure is amplifying the intrinsic radioprotective and pro-malignant effects exerted by CAFs Table . In a stConversely to the current view proposing a radiation-enhanced activation of CAFs, some studies document a loss of CAF pro-tumorigenic functions after irradiation Table . In an iIn clinical settings, radiotherapy continue being a safe and efficient way to treat most known solid malignancies . ExacerbScientific efforts over the last couple of decades have uncovered the important role played by the different elements of the tumor stroma in (radio)therapy outcomes. Cancer-associated fibroblasts have been proposed to participate significantly in tumor responses to radiotherapy. However, despite their prominent participation in tumor development and therapy resistance, the impact of RT on CAFs and the role of CAFs on RT outcomes remain elusive. Most existing literature in this field argue that radiation mediate changes in the mesenchymal components that favor tumor establishment and progression, however the impact that RT has on CAFs in vivo and the downstream effects of the potential RT-mediated changes remain controversial and still insufficiently investigated.A potential source of controversy may emerge from the unrecognized fact that CAFs and normal fibroblasts are different cell entities, behaving differently, and probably responding differently to radiation exposure even when considering that both may survive and turn senescent after exposure to substantial radiation doses. Collectively, most published studies on the effects of radiation performed with normal tissue fibroblasts or fibroblast cell lines demonstrate enhanced pro-tumorigenic functions from irradiated (senescent) cells induced primarily in a paracrine fashion, by increased secretion of soluble growth factors, inflammatory mediators, and proteolytic enzymes Table . MoreoveFindings on the impact of RT on CAFs and on the role of irradiated CAFs on tumor cell behavior are more controversial. While some studies claim that radiation exposure may affect CAF negatively through growth arrest and impaired mobility, others argue that exposure of CAFs to radiation can promote a more aggressive phenotype capable of conferring enhanced radio-resistance on tumor cells Table . Most puIn the clinics, radiotherapy is considered to be a safe and effective way to treat non-metastatic cancers with curative intent. Moreover, the use of RT in adjuvant and neoadjuvant settings has been proved to give better survival rates than surgery alone in many different tumor types . ConsideData for this review were identified by searches of MEDLINE, PubMed and references from relevant articles using search terms such as “cancer-associated fibroblasts”, “tumor microenvironment”, “radiation”, “radiotherapy”, “cell senescence”, “stress-induced senescence”. Only articles published between 1999 and 2022 have been included.


In recent years, the tumour microenvironment (TME) of solid tumours has attracted more and more attention from researchers, especially those non-tumour components such as immune cells. Infiltration of various immune cells causes tumour immune microenvironment (TIME) heterogeneity, and results in different therapeutic effects. Accumulating evidence showed that DNA methylation plays a crucial role in remodelling TIME and is associated with the response towards immune checkpoint inhibitors (ICIs). During carcinogenesis, DNA methylation profoundly changes, specifically, there is a global loss of DNA methylation and increased DNA methylation at the promoters of suppressor genes. Immune cell differentiation is disturbed, and exclusion of immune cells from the TME occurs at least in part due to DNA methylation reprogramming. Therefore, pharmaceutical interventions targeting DNA methylation are promising. DNA methyltransferase inhibitors (DNMTis) enhance antitumor immunity by inducing transcription of transposable elements and consequent viral mimicry. DNMTis upregulate the expression of tumour antigens, mediate immune cells recruitment and reactivate exhausted immune cells. In preclinical studies, DNMTis have shown synergistic effect when combined with immunotherapies, suggesting new strategies to treat refractory solid tumours. As mechanisms of cancer development have been gradually deciphered, tumour behaviours such as uncontrolled proliferation are considered to be the consequence of not only the accumulation of oncogenic alterations, but also epigenetic disruption. In fact, non-mutational epigenetic reprogramming has recently been included one of the fourteen hallmarks of cancer . EpigeneIn addition to the effects of tumour cells themselves, interactions between tumour cells and surrounding nontumor cells and tumour-infiltrating immune cells in the tumour microenvironment (TME) in particular, also play an indispensable role in cancer development. With advances in single-cell sequencing, an increasing number of immune cell subtypes in the TME have been identified, and researchers illustrated that immune cells can not only eradicate tumours but also be induced to take on a nonfunctional and even protumorigenic phenotype . InfiltrFurther studies have revealed that epigenetic factors participate in TIME regulation by affecting the expression of immune-related genes in both tumour cells and immune cells . DNA metDNA methylation is a ubiquitous modification throughout the genome, found in areas including promoters, enhancers, gene bodies and intergenic regions . A majorIn cancers, regional hypermethylation in promoters of tumour suppressor genes inhibits their expression and contributes to of cancer progression Fig.  25]. In. In25]. TET2 loss-of-function mutation has been recognised as a vital cause of malignancies, especially leukaemia, because it reduces the level of 5hmC, resulting in an inability to maintain an unmethylated state of promoters and enhancers as 5hmC does in normal cells .Fig.Fig79].F+ effector T cells. Patient outcome was also found to be negatively related to DNMT1 expression [CCL5 expression to escape the surveillance of effector cells by DNA methylation [To mediate migration into the TME, chemokines act as navigators to attract immune cells. Among chemokines, the chemokines CXC ligand (CXCL) 9 and CXCL10 have been consistently proven to be positively correlated with T-cell infiltration . Howeverpression . In addihylation . Apart fhylation . A similIn addition to impaired production of chemokines, the infiltration of immune cells can be negatively influenced by other mechanisms. Immune synapses are transient but necessary complexes that determine the activation of T cells. Immune synapse-related genes comprise immune checkpoint genes (ICGs) and costimulatory genes (CSGs). Disproportionate hypermethylation of CSGs and hypomethylation of ICGs are associated with impaired infiltration of T cells and worse survival . Moreove+ T cells and NK cells are more likely to infiltrate the TIME after administration of the DNMTi zebularine [Since DNA methylation has such a substantial effect on immune cell infiltration, DNMTis can naturally rescue the “cold” TIME. Preclinical models have demonstrated that CD8bularine . In anotbularine . DNMTi abularine . This in+ effector T cells in chronic viral infection and cancer results in gradual loss of effector cytokines and abrogation of cytotoxic capability, along with decreased proliferative ability and increased expression of inhibitory receptors such as programmed cell death 1 (PD-1), a state generally known as T-cell exhaustion [ex) cells, but the effect is not sustainable [ex cells fully responded to PD-1 blockade; [ex cells can be divided into progenitor Tex, transitory Tex and terminal Tex cells, and these cells exist on a trajectory; differentiation along the trajectory occurs in parallel with prolonged antigen exposure and a gradual increase in the expression of TOX, which is considered the key regulator of exhaustion. Progenitor Tex cells are more proliferative and characterised by higher expression of Tcf7 (like stem cells) than terminal Tex cells, and more importantly, terminal Tex cells are fixed in a dysfunctional state and unable to respond to ICI, whereas progenitor Tex cells are reprogrammable T cells also showed enhanced and prolonged antitumor activity, implying that DNMTi treatment might sensitise refractory tumours to immunotherapy and improve the prognosis of advanced cancer [To reverse the dysfunctional state, researchers have tried to impair the de novo methylation process. DNMT3A knockout was able to restore the proliferation and recall potential of terminal Td cancer , 92.+ T-cell activation and their cytolytic ability, and selected the subpopulation with high expression of granzyme B and perforin. Mechanistically, the cells overexpressed NFATc1 short isoforms associated with cytotoxicity and had increased chromatin accessibility at canonical recognition motifs of TFs involved in enhancing the transcriptional programme related to anti-tumour immunity [DNMTis such as decitabine can function in other ways to restore the activity of immune cells as well. As we have mentioned, DNA methylation in gene bodies is strongly correlated with high expression, and researchers have discovered that 3’-UTR DNA methylation is involved in the upregulation of immune-related genes, such as the immune checkpoint Havcr2. Decitabine inhibited this process and reinvigorated cytotoxic T cells . Loo et immunity . A singlimmunity . Moreoveimmunity .In summary, immune cell exhaustion is a mechanism by which tumour cells evade the immune system, and the primary driver is chronic antigenic stimulation. DNA methylation at least partly contributes to the maintenance of the exhausted state and irresponsiveness to ICIs, which can be reversed by DNMTi therapy. Moreover, the hypomethylation of checkpoint genes induced by DNMTis is likely to enhance ICI treatment by increasing target expressions, thereby supporting the combination of demethylating drugs and ICIs for the treatment of advanced solid tumours.Given the limited efficacy of ICIs in cancer patients, scientists have aimed to identify biomarkers and tools to evaluate the TIME and predict the efficacy of ICIs –99. FromThanks to advances in high-throughput technology and bioinformatics analysis, researchers are now able to use large-scale DNA methylation data to infer the status of TIME. MethylCIBERSORT is a DNA methylation-based bioinformatic approach that provides accurate estimates of cellular composition in the TME and identifies tumours as immune hot or cold . MeTIL cFinally, DNA methylation-based signature and scoring systems, such as EPIMMUNE, an epigenomic profile based on a microarray DNA methylation signature in metastatic NSCLC, have also been employed to evaluate the response to ICI treatment . DistincIn the future, these biomarkers and tools should be improved, enabling them to be applied across cancers and cancer stages, since many of them have only been tested and shown to be effective in specific stages and cancers. Moreover, with the help of single-cell technology, more markers of TILs and more specific subtypes related to immunotherapy should be identified to further improve the predictive ability.In the previous sections, we discussed how DNA demethylation reshapes the TIME, including altering the differentiation direction of immune cells, promoting immune cells infiltration toward the TIME and reviving exhausted immune cells. Such remodelling is ubiquitously observed in various solid tumours; furthermore, DNA methylation is relatively controllable due to its reversibility and there is ample experience in the treatment of haematological malignancies. In addition, preclinically, in syngeneic BALB/c mouse models, high immune reactivity and low tumour growth were achieved by combining 5-aza-20-deoxycytidine (5-AZA-CdR) with the anti-cytotoxic T lymphocyte antigen 4 (CTLA-4) monoclonal antibody (mAb) 9H10 . As a re+ T cells as well as classical monocytes in the TIME. Sufficient baseline levels of CD8+ T cells and CD20+ B cells and the presence of tertiary lymphoid structures were also associated with durable CBR, in line with trials using ICIs in melanoma and renal cell carcinoma [Ongoing and completed clinical trials have mainly been designed to include a DNMTi in combination with anti-PD-1/PD-L1/CTLA-4 blockade, and frequently used DNMTis include Aza, decitabine and the second-generation DNMTi guadecitabine. Despite all the advantages of combination treatment at the micro level, as discussed in previous sections, the outcomes of several clinical trials have been inconsistent. Generally, there has not been sufficient improvement in patient prognos. A study of pembrolizumab plus oral Aza CC-486 as treatment for advanced NSCLC patients found no improvement in PFS and OS . A similarcinoma , 121.Safety and tolerability are also important. In the trial in refractory NSCLC we mentioned above, more adverse events were observed in the combination group compared with the group that received pembrolizumab treatment alone, and these adverse events gave rise to dose interruptions, possibly impacting the response rate . However+ T cells expressed a large quantity of endogenous cancer–testis antigens, and were able to induce the generation of CTLs and NK cells, thereby inducing tumour regression in a few patients [In addition to these classical combination strategies, there are some novel targets and approaches Fig. . For inspatients . CAR T-cpatients . In precpatients , 125, sopatients . Some reTo sum up, present combination of ICI plus DNMTi does not live up to researchers’ expectation due to limited efficacy and unsatisfactory safety and tolerability. The underlying reason should be further studied as we have discussed and other approaches are worth exploration and clinical trials.Epigenetic regulation and immunotherapy are both research areas that are receiving increasing attention. In this review, we focused on one of the most common epigenetic modifications, DNA methylation, and its impacts on TIME remodelling in solid tumours. According to current studies, DNA methylation plays a significant role in controlling the differentiation, infiltration and activation status of immune cells. Tumours modulate DNA methylation to evade the surveillance of the immune system. For this reason, DNMTis have been applied in treatment, and studies have shown that they increase antitumor immunity by promoting ERV activation and viral-mimicry response. DNMTi treatment results in immune cell recruitment toward the TIME and reinvigoration of cytotoxic immune cells as well. Because of the many positive effects of DNMTi, combination treatment with DNMTis and immunotherapies in solid tumours is warranted. Nonetheless, the outcomes of clinical trials are still not ideal, including low response rate and a lack of safety and tolerability data.In the future, more targets and the functions of DNMTs and TETs in normal and cancer settings need to be identified. This will help us design epidrugs with enhanced targeting precision and efficacy and reduced side effects. Second, methylation levels vary both within and between lesions. With the assistance of single-cell and spatial omics analysis techniques, the methylation characteristics of different tumour lesions can be deciphered and targeted to maximise the effect. Third, apart from targeting writers of DNA methylation, readers and erasers can also be targeted. Moreover, as we have mentioned in this review, DNA methylation interacts with other kinds of epigenetic modifications. This suggests that the importance of each modification in different cancers and patients needs to be clarified, to select the most appropriate agents, and even to combine different agents together. Finally, it is necessary to determine the best dosage, delivery method and schedule in clinical settings.


Despite the multiple advances in therapy, cancer remains one of the most common causes of death globally. It is a systemic disease affecting people of all ages, originates at the level of single cells, which upon acquisition of mutations become neo-plastically transformed. Cell division is the biggest risk factor for accumulation of mutations , explainOur research has identified a new evolutionarily conserved RNAi-based form of cell death that targets essential survival genes, Death Induced by Survival gene Elimination (DISE) , 8. DISEin vitro, as well as in mice and in ovarian cancer patients [We hypothesize that DISE is part of a natural anti-cancer mechanism that is triggered when cells accumulate cancer causing mutations. So, if DISE is activated when cells sense a high mutational load, then most chemotherapeutic drugs should also trigger the DISE mechanism as they are genotoxic and acutely induce mutations. Indeed, our data show that different chemotherapeutic reagents resulted in induction of RISC-bound sRNAs and miRNAs that carry toxic 6mer seeds, suggesting that these drugs kill cancer cells, at least in part, by triggering DISE . We subspatients . We hypopatients , 20, allpatients .Our data are consistent with DISE being part of an ancient anti-cancer mechanism that could be used to treat cancer. The DISE mechanism therefore qualifies to be the ancient anti-cancer mechanism we postulated above. The fact that chemotherapy has features of DISE - both induce DNA damage , 22, is The discovery of DISE as a new anti-cancer mechanism holds great promise to eventually develop a pan cancer therapy. In order to convert this into an effective and safe form of therapy, however, several questions need to be addressed, most importantly whether conditions exist under which triggering of DISE affects normal cells.


Emerging science continues to establish the detrimental effects of malnutrition in acute neurological diseases such as traumatic brain injury, stroke, status epilepticus and anoxic brain injury. The primary pathological pathways responsible for secondary brain injury include neuroinflammation, catabolism, immune suppression and metabolic failure, and these are exacerbated by malnutrition. Given this, there is growing interest in novel nutritional interventions to promote neurological recovery after acute brain injury. In this review, we will describe how malnutrition impacts the biomolecular mechanisms of secondary brain injury in acute neurological disorders, and how nutritional status can be optimized in both pediatric and adult populations. We will further highlight emerging therapeutic approaches, including specialized diets that aim to resolve neuroinflammation, immunodeficiency and metabolic crisis, by providing pre-clinical and clinical evidence that their use promotes neurologic recovery. Using nutrition as a targeted treatment is appealing for several reasons that will be discussed. Given the high mortality and both short- and long-term morbidity associated with acute brain injuries, novel translational and clinical approaches are needed. Acute brain injury, including ischemic and hemorrhagic stroke, traumatic brain injury (TBI), anoxic brain injury and status epilepticus, are common causes of death and major disability both in the United States (US) and globally ,2. AlthoIn those with moderate-to-severe brain injury, nutritional optimization through the prevention of malnutrition and supplementation of select dietary therapies is an emerging field of interest to mitigate secondary brain injury and promote cellular recovery. Although proper nutrition is thought to promote recovery after brain injury, there are few evidence-based guidelines to standardize clinical practice. This is partially explained by a paucity of rigorous clinical trials in this field as well as conflicting results in the critical care literature . DespiteThe purpose of this comprehensive review is to describe how malnutrition impacts the biomolecular mechanisms of secondary brain injury after TBI, stroke and other neurological disorders and how nutritional status can be optimized in this population. We will further highlight emerging therapeutic approaches, including specialized diets that aim to resolve neuroinflammation and metabolic crisis after acute brain injury by providing pre-clinical and clinical evidence that their use promotes neurological recovery. Using nutrition as a targeted treatment is appealing for several reasons that will be discussed. This review will provide a shared model of malnutrition and nutritional optimization after acute brain injury with the aim of expediting translational research towards implementation and the improvement of patient outcomes.Malnutrition remains underrecognized in hospitalized patients, with approximately one-third developing malnutrition during their hospital course . Its preThe Skeleton in the Hospital Closet, which brought new attention to the prevalence and dangers of malnutrition among hospitalized patients [The recognition of malnutrition dates back five decades to the classic Butterworth’s publication patients . Since tpatients . The Eurpatients . More repatients . The staThe early identification of high-risk patients and the recognition of developing malnutrition are vital to supporting metabolic needs after TBI, stroke or other acute brain injury. Among hospitalized patients, it is associated with adverse outcomes, including poor wound healing, higher infection rates, increased length of hospital stay, increased hospital readmission rates, increased mortality and greater cost utilization compared to those without malnutrition ,14,15. CThe pathophysiology of acute brain injury is complex. Multiple mechanisms contribute to secondary brain injury, including ischemia, metabolic crisis, oxidative stress, immune dysfunction and blood–brain barrier (BBB) permeability. As we recently reviewed, neuroinflammation is the primary cellular mediator of secondary brain injury, both promoting and being sustained by these pathological mechanisms . Post-inTraumatic brain injury affects persons of all ages, genders and socioeconomic groups, accounting for 2.5 million US hospital visits annually , and is At a cellular level, biochemical changes begin within minutes of injury and progress over months-to-years . The priCurrent treatment options in TBI are limited. Given the association between malnutrition, inflammation and immunosuppression, nutritional optimization has been proposed as a promising therapy to restore post-TBI cellular homeostasis to prevent secondary brain injury . There iIschemic stroke, the most common form of acute stroke, is caused by the interruption of blood supply to the brain primarily by arterial thrombosis, embolism or systemic hypoperfusion. The final common pathway of threshold oxygen and glucose deprivation is neuronal apoptosis ; howeverCentral nervous system (CNS) disease-induced immunosuppression in the setting of neuroinflammation is of special interest and has been extensively studied in stroke models. The hyperactivation of immune cells by the inflammasome results in the exhaustion of mature leukocytes and the release of immature leukocytes that contribute to the development of post-stroke immunosuppression ,38. In aThe high prevalence and negative impact of post-stroke malnutrition, neuroinflammation and immunosuppression are of profound clinical importance. Ischemic stroke patients are at high risk of malnutrition during acute hospitalization due to cognitive impairment, a high occurrence of dysphagia and reduced physical mobility . ProteinSpontaneous non-traumatic intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH) are hemorrhagic stroke types that are associated with worse clinical outcomes compared to ischemic stroke . AlthougMortality from cardiac arrest affects over one million people worldwide annually . Anoxic Biomechanistically, the pathophysiology of anoxia involves a complex array of injury processes that include oxidative stress, mitochondrial dysfunction, and central hyperthermia . Neuroin2+-induced apoptosis seen after cardiac arrest to mitigate mitochondrial failure and metabolic crisis [Nutritional status is likely to impact these processes. In a mouse model of perinatal hypoxic-ischemic brain injury, Brandt et al. demonstrated that supplementation with various nutrient components including antioxidants was associated with reduced cytokine levels, microglial activation, the infiltration of immune cells and reduced lesion size . In stroc crisis .Epilepsy and status epilepticus (SE) are common in hospitalized patients. With an annual incidence of up to 41 per 100,000 patients and an overall mortality of 20%, seizures and SE remain an important cause of acute brain injury . DespiteChronic malnutrition has emerged as a significant factor in epilepsy development and seizure recurrence. This is especially true in developing countries, where malnutrition occurs in 22% of those with epilepsy . Pre-cliAcutely, SE increases superoxide species generation by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase through N-methyl-D-aspartate (NMDA) receptor activation . The oveIn SE, BBB function is negatively affected by malnutrition and neuroinflammation. Dysfunction in the BBB is associated with astroglial injury, increased neuronal excitability and epileptogenesis . ProteinKetogenesis is an important compensatory mechanism in SE that is negatively impacted by malnutrition. Imbalances in ketosis have been hypothesized to contribute to disorders in brain energy metabolism and ion channel function. Through ketosis, the liver uses long-chain fatty acids to synthesize three ketone bodies: β-hydroxybutyrate (βHB), acetoacetate and acetone . These sWhile the adult brain consumes 15–25% of total glucose metabolism during the resting state despite only weighing 2% of the human body, brain metabolic demands are far more dynamic during normal neurodevelopment and growth periods ,71. CombBeyond adaptive glucose metabolism, other micro- and macronutrients sustain normal brain development and function. Lactoferrin is one such factor that plays a protective role in postnatal physiology. Released in colostrum, this protein is a major beneficial factor in breastfeeding. Lactoferrin’s ability to protect against neuronal injury and sepsis through anti-apoptotic, anti-oxidative and antimicrobial properties has been demonstrated in pre-clinical models of perinatal inflammation and neonatal hypoxia-ischemia . Its proA major endogenous source of nutrients during neurodevelopment is the gut microbiota and its metabolic byproducts. Gastrointestinal tract microorganism colonization begins within a few hours of birth and typically matures by four years of age. Its makeup is determined in part by breastfeeding and other early nutritional factors and genetic conditions . Of specThere is a paucity of studies evaluating the effect of genetic nutritional and metabolic factors on outcomes in children after brain injury. As in adults, the apolipoprotein E4 genotype has been associated with worse outcomes in children with moderate-to-severe TBI. In one study of 70 children, those with the ApoE4 genotype were more likely to exhibit symptoms and have unfavorable neurological outcome after TBI ; howeverDetermining nutritional requirements early after pediatric brain injury is challenging, with discrepancies between measured and estimated energy expenditure (EEE) observed in children with TBI . A prospDetermining a patient’s nutritional requirements is challenging, especially in the ICU, as both underfeeding and overfeeding can lead to poor clinical outcomes. The variable metabolic response seen in acute brain injury can further confound this process, with head-injured patients needing an estimated 140% or more of baseline metabolic expenditure due to accelerated protein catabolism and increased metabolic rate . AlthougAppropriate nutrition prescription is essential in the treatment of acute brain injuries and takes into consideration the changing metabolic needs of individual patients. There has been increased interest in supplementing various nutrient components, whether in isolation or administered in combination, to modulate immune system function, resolve neuroinflammation and promote tissue repair after acute brain injuries. Patients with more severe injury from stroke, TBI or other diseases are often unable to take oral feeding, requiring the administration of enteral feeding formulations through a gastric tube. In clinical practice, specific diets and formulations are selected by a skilled dietary clinician based on clinical judgement as part of a multidisciplinary critical care team . The maip = 0.08) [After the initiation of EN, methods for increasing and monitoring nutritional adequacy have not been standardized. Clinically, achieving nutritional goals early to avoid malnutrition is paramount to supporting neurologic recovery. Taylor et al. reported a trend toward improved neurologic outcome 3 months after injury in patients who received EN at the goal rate early after admission, thus receiving a higher mean percentage of estimated energy requirements  . Recent  = 0.08) . Protein = 0.08) ,88. FreqDespite the evidence for the negative impact of malnutrition on critically ill patients with acute brain injury, the available data to support the precision monitoring of nutritional status in this patient population is lacking. Additional pre-clinical and clinical research is needed to define the optimal approach and monitoring strategies in patients with acute neurological disorders that will ensure proper nutritional support. Interventions that are widely available and feasible are most likely to be implemented as part of standard clinical practice.Although definitions in the literature vary, early feeding is generally defined as the initiation of EN within 24 to 48 h of ICU admission with late EN referring to initiation >48 h. In clinical practice, early EN is often recommended in the ICU, though with limited supporting evidence ,89,90. TIn the severe TBI population, multiple studies have shown that early initiation of feeding is associated with reduced mortality and infection risk and improved neurologic recovery. The biomechanistic effect has not been confirmed, but early feeding is hypothesized to introduce essential exogenous substrates that promote the maintenance of visceral protein and fat and improve immunocompetence . For genParenteral nutrition (PN) is designed to provide nutrients directly to blood through intravenous access in those with gastric dysmotility or absorptive disorders. Unless specifically indicated, EN is preferred to PN, as PN has been associated with increased infectious complications and longer hospital stays . A largeThe brain plays a significant role in the homeostatic regulation of glucose metabolism , but thiEarly clinical studies from general critically ill populations demonstrated that tightly controlling hyperglycemia with insulin was associated with improved outcomes ; howeverAlthough not universally standardized, some general recommendations regarding optimal nutritional support in the pediatric population exist. Current BTF Guidelines for the Management of Pediatric Severe TBI provide two primary recommendations: (1) early EN support within 72 h from injury is suggested to decrease mortality and improve outcomes, and (2) the standard use of immune-modulating diet is not recommended . In a prLike the adult population, the early use of PN is not supported. The Early versus Late Parenteral Nutrition in the Pediatric Intensive Care Unit (PEPaNIC) trial was a multicenter RCT which included 1440 term newborns to children 17 years of age admitted to a pediatric ICU, with about 8% diagnosed with TBI. The application of late PN resulted in fewer infections and a shorter duration of intensive care compared to early PN, regardless of age or diagnosis . This fiThe deleterious role of hyperglycemia has also been demonstrated in pediatric populations. In TBI, elevated admission blood glucose levels are associated with both short-term complications and long-term outcomes ,111,112.While KD has been applied for decades in children with drug-resistant or rare metabolic causes of epilepsy to reduce seizures, emerging science supports its use after acute brain injury. KD consists of high amounts of fats, moderate amounts of protein and very low quantities of carbohydrates. The theoretical mechanistic benefits are several, including the provision of an alternative energy substrate in ketone bodies, beneficial gut microbiome shifts, membrane stability and repair by providing essential lipids, antioxidant effects and the prevention of mitochondrial dysfunction . In rodeAstrocytes play a pivotal role in the regulation of brain oxidative metabolism and may benefit from exogenous ketone delivery. Under normal physiology, owing to their perivascular location, astrocytes are a prevalent site of glucose uptake and metabolism. The lactate they produce participates in the astrocyte-neuron shuttle to support neuronal oxidative metabolism . In addiThe anti-seizure effect of KD is mediated by increasing neuronal inhibition. This is hypothesized to occur through several mechanisms, including the alteration of GABA metabolism or GABA receptors. High levels of ketone bodies also decrease glutamate concentration in the synaptic cleft, resulting in reduced neuronal excitation ,126. In Research interest in the clinical efficacy of KD in other forms of acute brain injury is ongoing. Prospective clinical trials have been proposed for both acute spinal cord injury and TBI ,132. In Many scientific questions and practical limitations should be considered. Patient characteristics, including genetic factors, age, gender and race may impact the response to KD. Regarding age, both preclinical rodent models and human observational studies demonstrate that age modifies the effect of KD on ketone body formation after TBI ,135, whiThe incorporation of n-3 fatty acid supplementation in addition to standard nutritional support is a novel approach to optimize ICU nutrition and promote recovery after acute brain injury. Formulations for EN that contain n-3 fatty acid have been developed for their anti-inflammatory and pro-immune properties. Their use in modern ICUs is increasing; however, their effect has not been rigorously studied in patients with stroke, TBI or other acute brain injury.The biochemical properties of n-3 fatty acids provide rationale for its use. Endogenous bioactive lipids have diverse biological activities in regulating cell growth, adhesion, migration, signaling and cell death. Eicosanoid precursor fatty acids include n-3 polyunsaturated fatty acids (PUFAs) like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Their metabolites, termed specialized pro-resolving lipid mediators of inflammation (SPMs), are important regulators of inflammation. The generation of pro-resolving SPMs from n-3 and n-6 PUFAs is complex but begins with the enzymatic activity of cytosolic and calcium-independent phospholipase A2 at the phospholipid bilayer. The formation of bioactive PUFAs can also be enhanced through dietary supplementation, with widespread sites of action . At the Investigations on eicosanoid PUFAs in pre-clinical models are promising. In rat models of TBI, oral DHA administered pre-injury has been demonstrated to reduce oxidative stress, CD-68+ cells and caspase-3 levels and improve spatial learning ,144,145.The efficacy of n-3 and n-6 FAs or SPMs have not been rigorously tested in human populations. In TBI, the literature is limited to case studies or small series where high EPA and DHA supplementation was suggested as a potential contributor to good neurologic outcome ,152. To In addition to n-3 fatty acid supplementation, the use of immunonutrition to modulate immune function has recently been investigated in specific diseases, including acute brain injuries . AlthougDespite the proposed benefits of immunonutrition, it remains unclear which target diseases and populations are most likely to benefit from this intervention. Beyond cancer and trauma patients, the precise role of individual constituents of immunonutrition are under-investigated in stroke, TBI and other CNS injuries. In this context, the 2016 Society of Critical Care Medicine and the American Society for Enteral and Parenteral Nutrition (ASPEN) Guidelines for the Provision and Assessment of Nutrition Support Therapy in the Adult Critically Ill Patient suggest considering arginine-containing immune modulating formulations with EPA/DHA supplementation for patients admitted with TBI ,155. TheMineral elements, including but not limited to zinc and magnesium, have been investigated for their potential role in improving clinical outcomes in neurological diseases. While zinc deficiency may be harmful, supplementation has a controversial role in TBI given toxic levels that have been demonstrated following experimental injury and a possible contribution to excitotoxic cell death ,161. MagResearch highlighting the importance of maintaining gut microbiota homeostasis in neurological injury supports the modulation of immune, inflammatory and metabolic processes through the microbiota–gut–brain axis . The admComputerized tomography (CT) remains the initial diagnostic imaging modality of choice after acute brain injury due to its rapid acquisition; however, novel MRI modalities can provide a comprehensive assessment of brain anatomy, structural changes, anatomical and functional connectivity and metabolic characteristics. Advanced techniques that have been studied in acute brain injury include enhanced structural imaging, diffusion tensor imaging, vessel wall imaging, functional MRI, MR spectroscopy (MRS) and chemical exchange saturation transfer (CEST) imaging. These novel modalities remain largely investigational but can provide insight into the metabolic changes underlying secondary brain injury after stroke, TBI or other acute neurological disorders. Advanced neuroimaging techniques can also serve as real-time in vivo biomarkers in future translation research.MRS evaluates cerebral neurochemical status based on chemical shift and molecular environment and can detect both early and chronic changes. In a study of 32 patients with hyperacute MRS performed after acute ischemic stroke, elevations in lactate were measured even prior to the appearance of diffusion-weighted lesions that are the current gold standard for stroke diagnosis . After aPET imaging can also assess nutritional and metabolic status; however, it is not widely used for this purpose. Several tracers have been studied to detect specific CNS targets, most notably oxygen and glucose metabolism, cellular amino acid uptake and the activation of microglia and inflammation . After cThere is a paucity of data to support the use of other novel neuroimaging modalities for nutritional and metabolic assessment. A small study of 17 patients with mixed acute and chronic TBI demonstrated that CEST imaging could be used to detect cerebral acidosis secondary to excitotoxicity or ischemia, with results directly correlated with functional outcome . In pre-Cerebral microdialysis is an invasive device placed in brain parenchymal tissue to continuously sample extracellular interstitial fluid to measure specific important metabolites, including glucose, lactate, pyruvate and glutamate. It is a powerful research and clinical tool to assess the metabolic state of the CNS that previously could not be directly monitored in vivo in continuous fashion. The current role of CMD is as a clinical research tool and as part of cerebral multimodality monitoring following severe brain injury. The goal of CMD and multimodality monitoring is the early detection of supply and demand mismatch and resulting metabolic crisis to allow for prompt reversal and prevention of secondary brain injury . As prevEvidence of the influence of nutritional therapy on CMD parameters is inconsistent and lacking in the neurocritically ill patient population . In a reEmerging science continues to establish the detrimental effects of malnutrition and consequent neuroinflammation on the post-injury brain. Given this, novel clinical approaches targeting nutrition are needed. Proposed interventions, including KD, n-3 PUFA supplementation and immunonutrition, have extensive pre-clinical data demonstrating efficacy in alleviating inflammation, promoting metabolic homeostasis, reducing oxidate stress and attenuating pro-apoptotic signaling; however, rigorous study in prospective clinical trials is needed to determine if proposed interventions will have clinical effect. Nutritional formulations to support anti-inflammatory and immune system function are widely available, relatively inexpensive and largely considered safe, providing further rationale for their study and implementation into standard clinical practice. This is especially important in resource-limited environments, including global and military populations, where novel and feasible treatment options are desired.Many questions remain. Of greatest scientific priority, patient factors, including age, sex and other genetic and environmental factors that both predispose individuals to malnutrition as well as predict response to therapy, should be delineated. The further identification of novel nutritional biomarkers that accurately measure nutritional status or predict clinical outcomes will also aid in future translational research. Clinically, greater clarity is needed regarding which patient populations will most benefit from select nutritional interventions, as well as the timing, dose and duration needed to significantly impact clinical outcomes. Given the short and long-term morbidity and mortality associated with acute brain injury, novel and pragmatic clinical study is urgently needed to identify and implement optimal nutritional strategies that will improve CNS function.


Beyond genetics: modifications of nucleic acid and chromatin” gathers different contributions highlighting epigenetic modifications involved in diverse aspects of fundamental biological processes in plants. These studies shed light on the mechanisms as to how epigenetic modifications control auxin biosynthesis, cell pluripotency, floral transition, and DNA polymorphisms in model and non-model plant species.This Research Topic “Wang et al.) summarizes the epigenetic regulatory mechanisms of auxin biosynthesis. Indole-3-acetic acid (IAA), the major natural auxin, is synthesized through tryptophan-dependent and -independent pathways. The authors introduce that histone modifications, chromatin remodeling, DNA methylation and small RNAs all participate in regulation of auxin biosynthesis genes. YUCCA (YUC)  pathway to regulate auxin biosynthetic genes, while DNA methylation is involved in tissue-specific gene expression. Epigenetic modifications integrate responses to changes in the abiotic environment, such as shade avoidance and sensing ambient temperature, and auxin biosynthesis. The review points out that further investigations are needed to elucidate the epigenetic regulation of other auxin biosynthesis genes, regulation of tissue-specific expression patterns by various histone modifications, and the cross-talk and coordination of multiple epigenetic modifications.The first article of this Research Topic (CA (YUC)  family gMuller-Xing and Xing) shows the relationship between epigenetic modifications and cell pluripotency. The authors suggest that the epigenetic mechanisms play a crucial role in the initiation, maintenance, and determination of plant stem cells. Epigenetic factors control stem-cell fate by regulating either pluripotency genes directly or genes that maintain meristem organization. In shoot and root apical meristem (SAM and RAM), the pluripotency genes are controlled by histone variants deposition, histone modifications associated with gene activation or repression and chromatin remodeling complexes. Although chromatin modifiers are unable to bind DNA directly, many studies have found that intermediary transcription factors, pluripotency factors and cell cycle regulators can connect epigenetic factors and target DNA. Histone modifications are also involved in de novo stem cell formation through suppressing the pluripotency genes in differentiated tissue. Similarly, epigenetic silencing of several pluripotency genes also leads to stem cell determinacy in flower development. De novo stem cell regeneration contributes to organogenesis and relies on the removal of repressive H3K27me3 at pluripotency genes. It is still to be discovered how the epigenetic pathways corporate with each other and which upstream signals modulate their spatiotemporal specificity.The second article of this Research Topic  and then subjected to Fluorescence activated nuclei sorting (FANS). In the data analysis pipeline, strict alignment conditions and reproducibility checks are used to suit wheat and other plant species. This method requires fewer number of cells and robustly performs in diverse tissues, thus providing a new and versatile approach to epigenetic research field in wheat and potentially to other plant species as well.An improvement in studying chromatin states is a timely and concerning issue, thus a novel and optimized approach based on Fluorescence activated nuclei sorting (FANS) is proposed in Yu et al.). In this article, the authors describe the intraorganismal genetic heterogeneity (IGH) in Leymus chinensis. The authors first detected that in Leymus chinensis leaves, the nuclear genes (VIPP1 and XLG3) had higher nucleic acid polymorphism compared to the chloroplast genes (psbA and ndhH) by sanger sequencing. This higher nucleic acid polymorphism was further validated by high-throughput sequencing and the observation of normal cell size. By calculating the mutation frequencies, it was found that the mutation rates were predisposed. Next, the authors detected polymorphisms which started to accumulate from the seed stage and were subsequently reduced during development, meanwhile polymorphisms detected in leaves rarely resulted in amino acid changes, while they did in seeds. These observations in Leymus chinensis represent an exception to the pattern of accumulation of somatic mutations resulting in potential deleterious effects, and Leymus chinensis clearly shows strong ‘purifying selection’ to constrain the variation at the protein level.In addition to histone modifications, another study focuses on nuclear DNA diversity (In summary, this Research Topic covers various aspects of epigenetic regulation in auxin biosynthesis, cell pluripotency, floral transition and polymorphisms, from discoveries to method development. All these studies will undoubtedly promote further progress in this field. We hope that the reader will find this Research Topic a useful reference for the state of the art in the emerging field of epigenetics and cutting-edge methods. Moreover, we thank all authors and reviewers who contributed to this Research Topic.All authors listed have made a substantial, direct, and intellectual contribution to the work and approved it for publication.


Explore-exploit research has challenges in generalizability due to a limited theoretical basis of exploration and exploitation. Neuroimaging can help identify whether explore-exploit decisions use an opponent processing system to address this issue. Thus, we conducted a coordinate-based meta-analysis (N=23 studies) where we found activation in the dorsal lateral prefrontal cortex and anterior cingulate cortex during exploration versus exploitation, providing some evidence for opponent processing. However, the conjunction of explore-exploit decisions was associated with activation in the dorsal anterior cingulate cortex, dorsal medial prefrontal cortex, and anterior insula, suggesting that these brain regions do not engage in opponent processing. Further, exploratory analyses revealed heterogeneity in brain responses between task types during exploration and exploitation respectively. Coupled with results suggesting that activation in exploration and exploitation decisions is generally more similar than it is different suggests there remain significant challenges toward characterizing explore-exploit decision making. Nonetheless, dlPFC and ACC activation differentiate explore and exploit decisions and identifying these responses can help in targeted interventions aimed at manipulating these decisions. Explore-exploit problems are ubiquitous in many real-world situations such as staying in one line of employment or moving to another, keeping versus selling a stock, or trying out a new ice cream flavor or sticking with what you know. Situations where a person does not have full knowledge of their opportunities and outcomes have a fundamental dilemma whether to explore the space of possibilities available to them or exploit what they already know. Due to their prevalence in naturalistic settings, explore-exploit dilemmas have been extensively investigated, with an emphasis on whether certain people are consistently likely to over or underexploit. Over and under exploitation is especially interesting in psychological research as markers of psychopathology, such as among people with anxiety, compulsivity and smoking habits .Despite the interest in explore-exploit tasks, generating generalizable insights from decisions made in the lab has several major challenges. The first is that explore-exploit situations generally contain many independent variables that are difficult to control, such as the hidden payoffs of existing options, the number of options available to the participant, the strategies guiding exploration (random or directed), and the time horizons of the tasks . Even siMany tasks have been conceived to isolate explore-exploit decisions, though they mostly fall within two categories: foraging tasks  and n-arWhile there are canonical foraging and n-armed bandit tasks, there are many other variants of these tasks. One variation of the n-armed bandit task is the Horizon Task which runs for 15, 30, or 45 minutes was developed to discern if task length affects behavior . AnotherAnother approach may be to assess if economic or psychological differences can reliably differences in exploration or exploitation. In the context of temporal discounting problems there have been mixed findings, with one investigation finding associations between temporal discounting and directed exploration and no relationship between temporal discounting and random exploration  and anotOther kinds of individual difference measures have yielded somewhat more robust associations with exploratory or exploitative behaviors. Experiences of lifetime scarcity was related to decreased resource-maximizing decision-making  and indiseeExplore-exploit tasks lack behavioral convergence, contain a multitude of possible independent variables, and lack a coherent theory as to whether exploration and exploitation are a product of disparate versus unified mechanisms. With the lack of clarity as to the constructs and behaviors guiding explore-exploit decisions, another approach could examine the neurobiological factors that are consistent across explore-exploit choices. One notable challenge that could be observed neurobiologically is if explore-exploit tasks elicit a consistent or disparate set of responses during exploration versus exploitation  . We hypothesized that there will be convergence across explore-exploit studies in activation in the vmPFC, dlPFC, VS, ACC, and IPS while making explore-exploit decisions. These decisions are differentiated from the feedback phase where participants receive rewards based on their decision. The feedback phase does not constitute a strategic decision to explore or exploit based on preceding information. Next, we expected that the exploitation versus exploration decision would be associated with greater vmPFC, VS, ACC activity than the exploration phase and that the exploration phase will be associated with greater activation in the IPS and dlPFC than in the exploitation phase.Since we began this investigation, one group of researchers has conducted a meta-analysis of explore decisions  finding https://aspredicted.org/7hc7c.pdf), which detailed the hypotheses and analyses we intended to use. We conducted a systematic literature search to identify explore-exploit studies that used neuroimaging techniques. First, we identified search terms through identifying task names in several existing explore-exploit literature reviews . SDM was implemented using several steps to conduct analyses described in the SDM tutorial and manual. First, we imported the screened data by preparing folders with MNI text files that reported the clusters and t values for each coordinate. Exploration and exploitation decisions were grouped based on the constructs reported in each study. 12 studies reported explore>exploit and exploit>explore contrasts and were coded as exploration and exploitation respectively see . Other sNext, we created an SDM table with all the respective peak coordinates. We noted t-stats in the SDM table with respect to effect sizes and converted reported p and z stats using the SDM “convert peaks” function see . Then, wTo assess potential heterogeneity and potential bias in the CBMA results, we extracted funnel plots. We report the strength of evidence through multiple robustness considerations, study heterogeneity (I2 statistic), effect of small studies on the results (metabias) with resulting funnel plot asymmetry, and excess significance. The funnel plots are constructed through assessing the residual, or the weight each study has in the meta-analysis, with the size of its treatment effect, identified as precision on the y axis, though these tests must be interpreted with caution as publication bias can arise from multiple sources . All anaWe completed three meta-analyses that assessed activation across explore-exploit tasks, followed by activation specific to exploration and exploitation. First, we assessed the convergence across explore-exploit studies. This omnibus analysis would reveal common patterns of activation specific to making decisions in explore-exploit situations. We hypothesized that there will be convergence across explore-exploit studies in activation in the vmPFC, dlPFC, VS, ACC, and IPS. Our results indicate two significant clusters of activation in the left superior frontal gyrus, right nucleus accumbens (NAcc) see , Table 3seeWe conducted a CBMA contrasting the exploration and exploitation conditions across all the explore-exploit tasks. We hypothesized that the exploitation phase would be associated with greater vmPFC, VS, ACC activity than the exploration phase. Our analyses did not find any significant clusters of activation in the contrast between the exploit versus explore phases. Next, we hypothesized that the exploration phase would be associated with greater activation in the IPS and dlPFC than in the exploitation phase. Our results indicated six significant clusters of activation in the cerebellum, left and right dorsolateral prefrontal cortex, and left anterior cingulate cortex see, Table 3seeWe conducted a conjunction analysis across exploration and exploitation in the sample of studies we collected. We hypothesized that the conjunction of explore and exploit phases would be associated with activation in the IPS, dACC, and dlPFC. Supporting our hypothesis, we found common activation in the dACC in the conjunction between exploration and exploitation decisions see. In contWe followed up our pre-registered hypotheses by assessing if there are differences between activation in n-armed bandit tasks compared to other tasks during exploration and exploitation. If there are activation differences between tasks, this may suggest that these tasks are not eliciting consistent patterns of activation in exploration and exploitation as may be expected. During the exploration phase, we found that other tasks versus n-armed bandits resulted in three significant clusters, in the right precuneus, and the left and right supplementary motor areas see . We founNext, we followed up with assessing differences between n-armed bandit versus other tasks during the exploitation phase. During exploitation, the contrast between n-armed bandits versus other tasks yielded four significant clusters in the right rolandic operculum, left temporal gyrus, left median cingulate, and left paracentral gyrus see . None ofThis investigation conducted a coordinate-based meta-analysis of explore-exploit tasks. We included n-armed bandit and other types of explore-exploit tasks and analyzed them to assess patterns of activation consistent across explore-exploit decisions, unique to exploration and exploitation decisions respectively, and activation differences between tasks. First, we found consistent activation unique to exploration and exploitation decisions, with activation in the dlPFC, vmPFC, ACC, IPS, dmPFC, and VS. Second, we found stronger activation in the dlPFC and dACC during exploration versus exploitation. We found no differences between exploitation versus exploitation. Thirdly, we conducted an exploratory analysis assessing differences between n-armed bandits and foraging tasks during exploration and exploitation respectively. During exploitation, we found differences in activation in the PCC between n-armed bandits and other tasks. During exploitation, we found differences in activation in the AI and ACC between other tasks and n-armed bandits.Overall, our meta-analytic results support past findings that have identified critical regions involved in exploration and exploitation. Specifically, we found convergence in brain regions identified in the seminal study by Daw et al., 2006 with activation in the dlPFC, vmPFC, IPS, ACC, and VS unique to explore and exploit decisions. Nonetheless, this result may be tempered as the first cluster identified may have publication bias and report the presence of more significant findings than would be expected given the power of the tests. Further, the main body of the significant effects may be inflated due to effect sizes resultant from the incorporation of studies with small sample sizes. It is difficult to conclude whether there is actual publication bias as there are several possible explanations for this effect, including true heterogeneity within the effects measured . One intWhen we investigated the contrast between exploration and exploitation, we found stronger dlPFC and ACC activation during exploitation versus exploration, suggesting that these regions are part of opponent processes in explore-exploit decisions. These results are consistent with past findings , suggestHowever, there remain two large issues in interpreting exploration and exploitation through the lens of the opponent process model. The first is that there are more similarities than differences in activation across our results. Even when controlling for the effects of exploration and exploitation decisions specifically, our conjunction analyses reveal that exploration and exploitation generally elicit similar patterns of activation, particularly in the ACC, dmPFC, and AI. Extending on a previous meta-analysis suggests that these regions are not unique to exploration , but areSecondly, our exploratory analyses suggest that there remains substantial heterogeneity between tasks. This issue may speak to the lack of behavioral convergent validity between these tasks , which iAlthough our work has found that exploration and exploitation can be dissociated by dlPFC and ACC activation, we acknowledge our study has several notable limitations. First, while we have N=23 studies, this quantity is fairly low for a CBMA type meta-analysis, which has a common benchmark suggests a minimum of 17–20 Experiments . However, the exploratory CBMA of n-armed bandits versus other tasks during exploration and exploitation contrasted 13 versus 10 studies. As this sample size is below the benchmark, it should be considered exploratory. Nonetheless, there is a lack of clear guidance as to what are acceptable sample sizes using SDM, as they are highly contingent on the effects measured, number of participants, and whether thresholded images are included or not. Second, with the relatively small selection of studies, the inclusion of covariates such as age, sex distribution, and imaging parameters were not included. As more studies are completed, future researchers can assess the effects of these covariates.Other limitations extend beyond meta-analytic methods in assessing exploration and exploitation more generally. Explore-exploit tasks limit the manner information is presented, and a latent variable that may bias switching decisions includes the trend in information. Some studies have started to explore the effects of trends in information , though While acknowledging limitations for generalizing both behavioral and neural results resulting from exploration and exploitation, finding that the dlPFC and ACC reliably distinguish exploration and exploitation could fuel important future directions. First, a fruitful future direction includes modulating dlPFC responses, which are quite common in transcranial stimulation work. Since there are many links between dlPFC and psychopathology such as schizophrenia , anxietyIn summary, we conducted a CBMA meta-analysis of neuroimaging studies using explore-exploit tasks. We found that areas associated with executive control (dlPFC), attention , and reward (VS) are reflected in exploration and exploitation decisions. Exploration versus exploitation can be distinguished by greater activation in the dlPFC and ACC. Nonetheless, there remains substantial heterogeneity in brain responses due to task types, modulated by PCC, AI, and dmPFC activation while exploring and exploiting. Further, exploration and exploitation are associated with more similar than dissimilar patterns of activation in the AI, dmPFC, ACC, and VS. These results suggest that exploration and exploitation are not reliable opponent processes but are more of a product of the interaction of underlying physiological and psychological features guiding these decisions. Nonetheless, the finding that the dlPFC and ACC distinguish exploration and exploitation could serve as an important area of future research in cognitive neuroscience and psychopathology, as modulating these brain regions could shift how people explore and exploit.