Central venous catheters are ubiquitous in current medical practice in intensive care units and for long-term nutrition, chemotherapy, and antibiotic therapies. Umbilical venous catheters provide short-term central vascular access and are used in the neonatal period. This case presents sonographic and CT imaging findings of an intrahepatic and intracardiac calcified fibrin sheath following removal of a short-term umbilical venous catheter in a 32-day-old premature neonate. Umbilical venous catheters are a mainstay of advanced medical care in the neonatal intensive care unit (NICU), where neonates may require central venous access for total parenteral nutrition, antibiotics, hemodialysis, and other interventions. There are well-documented complications in the literature from central venous catheters (CVC), and specifically for umbilical venous catheters (UVC), including central line-associated bloodstream infections (CLABSIs), device failure, thrombosis, occlusion, migration, extravasation, and phlebitis . OcclusiA preterm infant delivered at Gestational Age (GA) of 31+1 weeks via caesarian section due to maternal preeclampsia required neonatal intensive care for respiratory distress. A 5Fr double-lumen UVC was placed on day 1 of life with the distal tip positioned at the inferior cavoatrial junction. Follow-up daily radiographs were obtained to monitor the position of the invasive devices  and the cardiorespiratory condition. These radiographs demonstrate cranial migration of the catheter with the tip in the right atrium on day 2. On day 5, the catheter tip was repositioned near the inferior cavoatrial junction  was placed for continued long-term total parenteral nutrition (TPN), and the umbilical venous catheter was removed. The patient continued to require neonatal intensive care and had a complicated course requiring multiple intubations. On day 32, a transthoracic echocardiogram was obtained to evaluate pulmonary hypertension as a potential cause of the patient’s ongoing respiratory difficulties. This exam demonstrated a hyperechoic focus along the interatrial septum which represented a fibrin sheath . This exam demonstrated a curvilinear hyperdensity with attenuation of 333 Hounsfield units extending from the intrahepatic inferior vena cava (IVC) to the right atrium.An ultrasound was performed and corroborated this finding. It demonstrated a curvilinear hyperechoic structure without significant posterior shadowing extending from the central left hepatic vein through the IVC to the right atrium Figure .The patient remained in the neonatal intensive care unit (NICU) and obtained a follow-up echocardiogram on day 61, which demonstrated similar findings to prior. Anticoagulation therapy was deferred because the patient was scheduled to undergo a lung biopsy. The patient’s respiratory status improved and the patient did not undergo a biopsy and was ultimately discharged home after more than 3 months in the NICU. A follow-up outpatient echocardiogram was performed on day 127 of life, demonstrating a hyperechoic focus along the interatrial septum. There was no residual calcified fibrin sheath in the right atrium or IVC Figure . No furtUmbilical venous catheters provide short-term central venous access in the neonatal period. If long-term vascular access is required, a PICC is preferred . Two recCatheter-associated fibrin sheath formation has been described in swine models with the development of a cellular covering along the catheter from activation of the coagulation cascade. This covering is made of smooth muscle cells, thrombus, endothelial cells, and plasma proteins like fibrinogen after the first week. As time progresses, pathophysiological changes like smooth muscle and endothelial cell proliferation occur and ultimately the formation of collagen and fibrous connective tissue .CVC-associated fibrin sheaths are very common in the adult population, with one study of 133 hemodialysis patients reporting the formation of fibrin sheaths in 47% at the time of removal . In pediIn the previously reported cases, the clinical severity of a retained fibrin sheath varies. Some were asymptomatic and observed over time, others were asymptomatic and treated with anticoagulation, one resulted in an asymptomatic pulmonary embolism, and multiple required cardiac surgery for removal of fibrin sheaths Table . This paRetained fibrin sheaths are relatively rare complications of central venous catheters and are typically involved in long-term catheters. These sheaths can have an innocuous clinical course, but in some cases may require invasive surgery for removal. This is the first case report in English literature describing a retained fibrin sheath in a neonate following removal of a UVC with both CT and sonographic findings. This case highlights the fact that fibrin sheaths can form after short-term use (8 days in this case) in neonates and provides additional support for the earliest possible removal of central venous catheters, including umbilical venous catheters.


Clinical evidence suggests that nebulized colistimethate sodium (CMS) has benefits for treating lower respiratory tract infections caused by multidrug-resistant Gram-negative bacteria (GNB). Colistin is positively charged, while CMS is negatively charged, and both have a high molecular mass and are hydrophilic. These physico-chemical characteristics impair crossing of the alveolo-capillary membrane but enable the disruption of the bacterial wall of GNB and the aggregation of the circulating lipopolysaccharide. Intravenous CMS is rapidly cleared by glomerular filtration and tubular excretion, and 20–25% is spontaneously hydrolyzed to colistin. Urine colistin is substantially reabsorbed by tubular cells and eliminated by biliary excretion. Colistin is a concentration-dependent antibiotic with post-antibiotic and inoculum effects. As CMS conversion to colistin is slower than its renal clearance, intravenous administration can lead to low plasma and lung colistin concentrations that risk treatment failure. Following nebulization of high doses, colistin  lung tissue concentrations are > five times minimum inhibitory concentration (MIC) of GNB in regions with multiple foci of bronchopneumonia and in the range of MIC breakpoints in regions with confluent pneumonia. Future research should include: (1) experimental studies using lung microdialysis to assess the PK/PD in the interstitial fluid of the lung following nebulization of high doses of colistin; (2) superiority multicenter randomized controlled trials comparing nebulized and intravenous CMS in patients with pandrug-resistant GNB ventilator-associated pneumonia and ventilator-associated tracheobronchitis; (3) non-inferiority multicenter randomized controlled trials comparing nebulized CMS to intravenous new cephalosporines/ß-lactamase inhibitors in patients with extensive drug-resistant GNB ventilator-associated pneumonia and ventilator-associated tracheobronchitis. Bacillus aerosporus that were identified in 1946 from the soil of market gardens in England [Enterobacterales, Pseudomonas aeruginosa and Acinetobacter baumannii. CMS is an inexpensive antibiotic massively used worldwide and considered as an essential antimicrobial agent by the World Health Organization [Polymyxins are non-ribosomal, cyclic oligopeptide antimicrobials, produced by the Gram-positive, spore-forming rod nization . The CMSThis narrative review is focused on nebulized CMS as a treatment of ventilator-associated pneumonia (VAP) in critically ill patients. It has three aims: (1) to report the historical background supporting its use in critically ill patients; (2) to describe the complex and partially unknown PK/PD of intravenous and nebulized CMS; (3) to suggest future research priorities for CMS nebulization in patients with VAP caused by extensive drug-resistant (XDR) GNB.Oral colistin was first used in veterinary medicine in 1952 and is still widely used in pigs to treat or prevent intestinal infections . The worp < 0.001). Over the two-year study period, there was no emergence of CMS resistance. Mortality was not significantly influenced by the prophylactic administration of CMS. These results were confirmed 20 years later in a single-center, two-arm, randomized, open-label, controlled trial performed in 186 critically ill patients on mechanical ventilation for > 48 h [From the early 1970s to the mid-1990s, polymyxins were topically administered for prophylaxis of GNB pneumonia. In 744 spontaneously breathing or mechanically ventilated critically ill patients, polymyxin B was sprayed into the posterior pharynx and/or instilled in the endotracheal tube eight times a day ,6. This r > 48 h . Eighty P. aeruginosa and A. baumannii, with extensive drug resistance (XDR) became the most common microorganisms causing VAP in Europe and Asia [In the early 2000s, intravenous ,14 and nand Asia ,17, and A. baumannii . The N-terminal fatty acyl chain is crucial for the antimicrobial activity of polymyxins: it allows the disruption of the lipid A fatty acyl chains of the lipopolysaccharides (LPS) component of the outer membrane of GNB [As shown in e of GNB . The pol++ or Mg++ associated with lipid A phosphodiesters serve as bridges between adjacent LPS molecules and stabilize the outer membrane  is another mechanism of colistin resistance. Mcr genes encode a phosphoethanolamine transferase leading to the addition of a phosphoethanolamine moiety to the lipid A of LPS, increasing the cationic charges on LPS and, consequently, limiting the binding of colistin to LPS. Up to now, nine mcr alleles have been reported, mcr-1 to mcr-9 [mcr-1 was reported on all continents after being initially identified from chickens in China three decades ago when colistin started to be used in food-producing animals [Enterobacterales. In swine industrial production, colistin is administered by feed and drinking water in the entire farm, involving indiscriminately both healthy animals and animals with clinical symptoms. In 2016, the European Medicines Agency recommended to ban colistin therapies for prophylactic purposes, as it carries a high risk of the emergence of resistance. Despite this recommendation, prophylactic administration of colistin is still a common practice worldwide, especially in Asia, to support farm animal production. Interestingly, in the Netherlands, colistin is routinely used in selective digestive decontamination regimens without a report of alarming rates of resistance.The horizontal transfer of plasmid-borne genes of the family to mcr-9 . As show animals . The mai animals . In pigsCMS is a complex mixture of up to ~30 methanesulfonated derivatives produced by the reaction of colistin with formaldehyde and sodium bisulfite. The composition of CMS pharmaceutical products may vary from brand-to-brand and even from batch-to-batch. CMS acts as a polyanionic inactive prodrug that is less nephrotoxic than colistin sulfate. As shown in As shown in Because renal elimination of CMS is much more rapid than its spontaneous conversion to colistin, it is necessary to administer about 4–5 times the amount of CMS to generate colistin plasma concentrations above the minimum inhibitory concentrations required for a bactericidal activity. As shown in Pseudomonas aeruginosa inoculation pneumonia [Pharmacokinetics of nebulized CMS are incompletely understood mainly because of the difficulty to assessing lung interstitial concentrations in human studies. Indeed, the contamination of the bronchoscope by bronchial secretions during the bronchoalveolar procedure skews the interpretation of epithelial lining fluid (ELF) concentrations following antibiotic nebulization ,72 and lneumonia . Lung honeumonia .Nebulization of high doses of CMS results in high lung tissue colistin concentrations with correspondingly low plasma colistin concentrations (< 2 µg/mL) c suggestfAUC/MIC) best describes the antimicrobial activity of colistin [P. aeruginosa and A. baumannii, an fAUC/MIC value of 7.4–13.7 and 7.4–17.6 is required for a 2 log10 reduction in bacterial load. Following intravenous administration, 2 log10 killing in the lungs cannot be achieved with doses as high as 50,000/kg, likely due to limited drug exposure in the lungs. Experimental and clinical PK/PD data clearly indicate that intravenous colistin (and CMS) has limited efficacy against respiratory tract infections [As shown in colistin . For MDRfections . Pharmacfections .Neuromuscular toxicity, nephrotoxicity and bronchoconstriction are most common adverse events associated with CMS administration. Polymyxin-induced neuropathy and myopathy is rarely seen . NephrotCell culture and animal studies demonstrate that colistin accumulates in renal tubular cells. Urinary colistin is reabsorbed via active uptake mechanisms mediated by megalin and oligopetide transporter 2 . The resA meta-analysis was performed on 12 studies including 373 patients treated by nebulized CMS monotherapy for VAP and ventilator-associated tracheobronchitis. Acute kidney injury was observed in 20% of treated patients compared to 31% in control patients. Neuromuscular toxicity was observed in 3% of patients and bronchospasm in 2% of patients .2O; (5) the administration of a short-acting sedative agent to ensure coordination between the patient and the ventilator; (6) the insertion of a filter on the expiratory limb to protect the ventilator flow device. This filter should be changed between each nebulization to avoid expiratory flow obstruction; (7) the removal of heat and moisture exchanger and the interruption of the conventional heated humidifier to avoid massive trapping and condensation of aerosolized particles.Optimizing lung deposition of CMS to provide effective bacterial killing in critically ill patients with VAP and VAT requires a specific nebulization strategy including ,53,94: . Toxic degradation products resulting from the long conservation of the aqueous solution were considered as responsible for the fatal outcome [CMS and colistin are not stable in various aqueous media ,95. It i outcome .Following intravenous administration, 70% of a CMS dose is rapidly cleared by the kidney, whereas 20–25% is slowly hydrolyzed to colistin through a process that takes more than 36 h. Penetration into all organs except the kidneys and biliary tract is also quite limited. PKPD studies indicate that it is difficult to reach bactericidal colistin concentrations at the site of infection in patients with normal renal function without exceeding the recommended plasma concentrations of 2 mg/L, above which the risk of nephrotoxicity markedly increases . MicrodiAs systemic diffusion of nebulized CMS is limited and its hydrolysis in colistin is slow, plasma concentrations of colistin following CMS nebulization remain lower than minimal inhibitory concentrations in the majority of patients b,d. TherEscherichia coli [Pseudomonas aeruginosa [Pseudomonas aeruginosa [−1 in consolidated lung areas. Among 13 lung segments with consolidation, nine had tissue lung concentrations ≥ 2 µg∙g−1, the MIC of the inoculated Pseudomonas aeruginosa strain. As lung homogenate tissue concentrations markedly underestimate interstitial space fluid concentrations, it can be hypothesized that true concentrations at the site of infection were higher. As for many nebulized antibiotics, colistin tissue concentrations decrease with the degree of aeration loss [Another issue concerns the diffusion of nebulized CMS into consolidated lung areas characterizing confluent and lobar VAP. In theory, the lack of lung aeration should preclude the penetration of nebulized CMS into the consolidated infected lung parenchyma. Interestingly, experimental studies have repeatedly shown that, although lung tissue concentrations decrease with the aeration loss, they remain largely above minimal inhibitory concentrations in the majority of animals with consolidated infected lung regions ,99,100. hia coli ,99; (2) ruginosa ; (3) higruginosa . After tion loss  but remaion loss . The exaion loss , as wellPseudomonas aeruginosa and treated by high-dose nebulized amikacin and/or Fosfomycin combined or not with intravenous meropenem, tracheal antibiotic concentrations were compared to lung tissue [−1) [Last but not least, it is difficult to assess interstitial space fluid concentrations from epithelial lining fluid concentrations measured from a bronchoalveolar lavage sample ,72. In ag tissue . Due to sue [−1) . These dAs the treatment efficiency of intravenous CMS is frequently suboptimal, adjunctive therapy (nebulization + intravenous CMS) appears unwarranted in non-bacteremic VAP. Compared to intravenous CMS alone, adjunctive therapy increases lung tissue concentrations without reducing plasma concentrations. Therefore, it likely improves efficacy without decreasing toxicity risk. Compared to adjunctive therapy, substitution therapy  markedly reduces colistin plasma concentrations and decreases the risk of toxicity, as shown in a recent meta-analysis . TherefoAssessing intrapulmonary PKPD of nebulized CMS and colistin is quasi impossible in patients with VAP, because the bronchoalveolar samples serving for measuring epithelial lining fluid concentrations are contaminated by nebulized CMS and colistin ,73,75,76Future experimental studies using intrapulmonary microdialysis should describe the time-dependent profile of CMS and colistin interstitial space fluid concentrations after the nebulization of the first and the following nebulizations of 200,000 IU/kg. In parallel, systemic, biliary and urinary CMS and colistin concentrations should be assessed. Another experiment should verify that increasing concentrations of nebulized CMS  are associated with increasing interstitial space fluid concentrations of colistin. Again, systemic, biliary and urinary CMS and colistin concentrations should be assessed in parallel.Klebsiella pneumoniae producing carbapenemase and oxacillinase and ceftolozane tazobactam against Pseudomonas aeruginosa with non-enzyme mediated carbapenem resistance. Cefiderocol or eravacycline are active against carbapenem-resistant Acinetobacter baumannii.A number of new antimicrobial agents are now available with activity against MDR GNB. Ceftazidime avibactam and ceftolozane tazobactam are active against MDR-XDR Enterobacterales . Ceftazidime avibactam and ceftolozane tazobactam are active against MDR-XDR Enterobacterales. Ceftazidime avibactam is active against CMS remains a key agent in the treatment of VAP and VAT caused by MDR GNB, but the optimal regimen is currently unclear. Randomized controlled trials are urgently required to identify optimal treatment strategies for patients with VAP and VAT caused by MDR GNB. Superiority multicenter RCTs comparing nebulized CMS alone with the intravenous administration of CMS are required to guide treatment when new cephalosporines/ß-lactamase inhibitors are not available or when VAP or VAT is caused by XDR GNB resistant to the new cephalosporines/ß-lactamase inhibitors. Where new cephalosporines/ß-lactamase inhibitors are available, non-inferiority multicenter RCTs should compare the nebulization of CMS alone with the parenteral administration of new cephalosporines/ß-lactamase inhibitors. Expected benefits from nebulized CMS are a more rapid clinical cure, a reduction in the duration of mechanical ventilation, less nephrotoxicity and a shorter duration of antibiotic administration. As lung deposition of nebulized CMS decreases with lung aeration , patientAlthough well-designed multicenter RCTs are lacking, there is a body of evidence suggesting that nebulized CMS is efficient for treating lower respiratory tract infections caused by MDR GNB. The complex PKPD of the intravenous prodrug CMS, characterized by a rapid renal elimination and a slow hydrolysis in active colistin, advocates for nebulization rather than intravenous administration. Experimental studies using intrapulmonary microdialysis are urgently needed to characterize lung PKPD and optimize CMS nebulization, but preliminary studies suggested nebulization of CMS results in high intrapulmonary concentration of colistin. Future superiority multicenter RCTs should compare high doses of nebulized CMS to high doses of intravenous CMS in VAP and VAT caused by extensive drug-resistant GNB not sensitive to aminoglycosides and/or new cephalosporines/ß-lactamase inhibitors. Noninferiority multicenter RCTs should compare high doses of nebulized CMS alone to new cephalosporines/ß-lactamase inhibitors in VAP and VAT caused by extensive drug-resistant GNB.


The use of mobile phones has widely increased over the last two decades. Mobile phones produce a radiofrequency electromagnetic field (RF-EMF), a form of non-ionizing radiation. In contrast to the ionizing radiation proven to cause DNA damage, the harmful effects of non-ionizing radiation on the human body have not been discovered yet. The thyroid gland is among the most susceptible organs to mobile phone radiation due to its location in the anterior neck. Our purpose in this literature review is to explore the effects of the electromagnetic field (EMF), especially radiofrequency emitted from mobile phones, on thyroid hormones and thyroid gland histopathology. We searched PubMed and Google Scholar databases for relevant studies published after the year 2000, using the following keywords: ‘cell phones', ‘mobile phones', ‘telephones', ‘electromagnetic fields', ‘radiofrequency radiation', ‘microwaves', ‘thyroid gland', ‘thyroid hormones', and ‘thyroid cancer'. Our review revealed that mobile phone radiofrequency radiation (RFR) might be associated with thyroid gland insufficiency and alterations in serum thyroid hormone levels, with a possible disruption in the hypothalamic-pituitary-thyroid axis. The review also showed histopathological changes in the thyroid gland follicles after exposure of rats to non-ionizing radiation. The results were directly related to the amount and duration of exposure to EMF radiation. Further human studies exploring thyroid gland hormones, microscopic morphology, and thyroid cancer are highly recommended for future researches. Robert O. Becker 1923 − 2008), a researcher from the United States (US) in electromedicine and a Nobel Prize winner 3 − 2008,. ElectroNon-ionizing forms of radiation include lower frequencies on the electromagnetic spectrum and are not proven to cause DNA damage directly Figure  . ExamplSeveral pieces of research were conducted to study the health effects of ELF-EMF and RF-EMFs. One of the most pronounced effects found was the heating of human tissues, i.e., the thermal effect . When exSome health-related concerns have increased along with the revolution of mobile phone usage. These include male infertility, cognitive and memory deficits, headaches, sleep problems, and increased cancer risk . AccordiThe purpose of this review is to explore the effects of EMF, especially radiofrequency radiation (RFR) emitted from mobile phones, on the thyroid gland hormones and thyroid tissue. We aimed to look at alterations in thyroid hormone levels upon exposure of the thyroid gland to non-ionizing radiation for a specific duration. Additionally, we reviewed the histopathological effects of non-ionizing radiation on the thyroid gland follicular tissue. We also wanted to determine whether RF-EMF or ELF-EMF is related to increased thyroid insufficiency in recent years. Therefore, we searched human, animal, and in-vitro studies in PubMed and Google Scholar databases and included studies done after the year 2000 using the following keywords: ‘cell phones', ‘mobile phones', ‘telephones', ‘electromagnetic fields', ‘radiofrequency radiation', ‘microwaves', ‘thyroid gland', ‘thyroid hormones', and ‘thyroid cancer'. We retrieved a total of 138 articles and included only the articles that directly tested the association between non-ionizing radiation exposure and the thyroid gland. We ended up with 28 articles that were most relevant to our topic. Of these articles, six were observational human studies, 18 were animal studies, three were in-vitro studies, and one was a systematic review of mixed studies.Mobile phones and thyroid gland hormonesThyroid gland hormones, including triiodothyronine T3) and thyroxine (T4), are essential hormones for regulating the basal metabolic rate (BMR) of the body. Of the thyroid gland secretions, 90% are T4 that later converts into T3, the more potent and active form of thyroid hormones [ and thyrThyroid Hormones in Human StudiesSeveral studies investigated the effects of RFR emitted by global systems for mobile communications (GSM) mobile phones on serum thyroid hormone levels. In a medical college in South India, Baby et al. (2017) performed a cross-sectional study on 83 undergraduate students . SurveysBergamaschi et al. (2004) performed a cross-sectional study to analyze the effects of cell phones on the thyroid gland function of 2598 employees . BergamaThyroid Hormones in Animal StudiesMany animal studies sought to discover the association between non-ionizing radiation and thyroid hormones. Izmest'eva et al. (2003) performed an experimental animal study by exposing laboratory rats to 12 minutes of microwave radiation using a SAR value of 30W/Kg, a very high absorption rate . The stuIn the study of Koyu et al. 2005), 30 rats were used and divided into groups. The exposure group was exposed to 900 MHz EMF for 30min per day for one month . Results05, 30 raThe majority of studies point towards an inhibitory effect of RFR on the HPT axis or thyroid tissue, leading to thyroid insufficiency, especially over the long term. In contrast, few studies did not find significant results. Kim et al. 2013) used a whole-body exposure system with a reverberation chamber to emit Radiofrequency Identification (RFID) on laboratory rats . However3 used a Mobile phones and thyroid gland histopathologyThe thyroid gland is composed of follicles, which are spherical structures lined by cuboidal cells, i.e., follicular cells, and are responsible for thyroid hormone production. In the middle of a follicle, there is colloidal material composed of thyroglobulin . In addiThyroid Gland Histopathological Changes Due to 900 MHz EMFMany animal studies explored the effects of RFR at the microscopic level of the thyroid gland tissue. Eşmekaya et al. (2010) exposed animal rats to 900MHz for three weeks and observed the histopathologic changes in the thyroid gland. The study found significant pathological changes consistent with hypothyroidism . There wThe histopathologic changes induced by RFR are not limited to a resting follicular state. Most animal studies revealed hyperstimulation of the thyroid follicles. Shaukat et al.  exposed animal rats to 50 missed calls per day emitted from 900/1800 MHz GSM mobile phones over two months. The study found histopathological changes in the thyroid gland consistent with gland hyperstimulation ,27. The Cellular Stress Induced by EMFHeat shock proteins (HSPs) are cellular chaperones that regulate cellular protein folding in response to external stressors or increased cellular heat. Their presence is crucial for preventing various diseases and cancerous changes. Agustiño et al. (2019) found that HSP-90 and HSP-70 significantly decreased (P<0.01) after 90 minutes of exposure to 2.45GHz . HoweverHussien et al. (2020) decided to expose 30 rats to cell phone radiation for 30 days and measure thyroid tissue oxidative stress, thyroid functions, and plasma nesfatin-1 levels [Studies observed that mobile phones can exert their deleterious effects on the thyroid gland through thermal and non-thermal effects by exciting cellular receptors and causing disruption in the microtubules between cells . The nonThyroid Gland Histopathological Changes Due to 50Hz ELF-EMFThe effects of extremely low-frequency EMF (ELF-EMF) on thyroid gland histology were also studied in the literature. Rajkovic et al. (2001) observed the thyroid glands of animal rats under light and electron microscopes upon exposure to 50 Hz ELF-EMF . After tAnother study concluded that EMF radiation acts as a stress factor on the degranulation of mast cells , as therAre mobile phones related to increased trends of thyroid gland disorders and thyroid cancer?Studies about the relationship between RFR and thyroid cancer are lacking, and future research is required to find any association. Carlberg et al. (2020) reviewed the Swedish Cancer Register to study the thyroid cancer trends between 1970 and 2017 in the Nordic countries . The stuChildren under 16 years of age are more prone to the long-term harmful effects of radiation exposure . Lu & MuLimitationsMost of the studies in this review conducted their experiments on animal rats in laboratory settings, using specific radiation frequencies to mimic mobile phone radiation on the thyroid glands of animals. Studying the effects of radiation on the thyroid glands of humans and taking human thyroid biopsies would require invasive procedures. In addition, conducting clinical trials on humans would require ethical considerations. Moreover, the mobile phone industry is an emerging research area with only limited data available in databases. Mobile phones can be viewed as cigarettes when they first emerged into the market; it took researchers several decades to determine the association between cigarette smoke and cancer. Thus, time might be the only determinant of an association between prolonged exposure to non-ionizing radiation and thyroid diseases or cancers in humans.Recommendations for mobile phone usersDuring outgoing calls, mobile phones emit much more radiation than incoming calls . TherefoThis article aimed to explore the effects of RF-EMF and ELF-EMF on the thyroid gland hormones and histopathology. Studies collected in this review showed that GSM mobile phone RFR could be associated with alterations in T3, T4, and TSH serum hormone levels. EMF emitted from mobile phones could disrupt the function of the HPT axis and lead to thyroid insufficiency. In addition, EMF could lead to hyperstimulation of thyroid gland follicles, causing oxidative stress and apoptosis of follicular cells. Most studies revealed a proportional correlation between thyroid gland dysfunction and the exposure duration, intensity, and SAR value of radiation. Moreover, non-ionizing radiation was seen to be significantly associated with histopathological changes in the thyroid gland follicles. The exposure duration and intensity also determined the degree of morphological damage occurring in the thyroid gland tissue. Non-ionizing EMF radiation might be responsible for the recent increase in the incidence of thyroid insufficiency and cancer in the general population. However, not enough data was found related to thyroid cancer risk with non-ionizing radiation exposure. Keeping in mind the ethical considerations, we recommend future observational studies be conducted on human beings to further explore the association of non-ionizing radiation emitted from mobile phones on the thyroid gland's hormones, histopathology, and cancers over the long term.


The rumen is the critical organ mediating nutrient uptake and use in cattle. Health development is essential to ensure animal feed efficiency. In this report, we present an analysis of gene expression dynamic in rumen epithelium during the transition from pre-ruminant to ruminant in cattle fed with hay or concentrated diets at weaning. The global shifts in gene expression and correlated transcription factors activities indicate transcriptional reprogramming during weaning. Transcriptional reprogramming in rumen epithelial tissue reflects critical nutrient-gene interactions occurring during the developmental progression. The results unveiled that nutrient-gene interactions compel transcriptional reprogramming. Our findings also suggest that this transcriptional reprogramming is the molecular basis of the transitional development of pre-ruminant to the ruminant in cattle.We present an analysis of transcriptomic dynamics in rumen epithelium of 18 Holstein calves during the transition from pre-rumination to rumination in cattle-fed hay or concentrated diets at weaning. Three calves each were euthanized at 14 and 42 d of age to exemplify preweaning, and six calves each were provided diets of either milk replacer and grass hay or calf starter to introduce weaning. The two distinct phases of rumen development and function in cattle are tightly regulated by a series of signaling events and clusters of effectors on critical pathways. The dietary shift from liquid to solid feeds prompted the shifting of gene activity. The number of differentially expressed genes increased significantly after weaning. Bioinformatic analysis revealed gene activity shifts underline the functional transitions in the ruminal epithelium and signify the transcriptomic reprogramming. Gene ontogeny (GO) term enrichment shows extensively activated biological functions of differentially expressed genes in the ruminal epithelium after weaning were predominant metabolic functions. The transcriptomic reprogramming signifies a correlation between gene activity and changes in metabolism and energy production in the rumen epithelium, which occur at weaning when transitioning from glucose use to VFA use by epithelium during the weaning. Weaning is the process of gradually introducing an infant human or another neonatal mammal to its adult diet while withdrawing its mother’s milk supply. The forestomach compartments of ruminants are underdeveloped at birth. They are virtually non-functioning, making neonatal ruminant digestion like that of monogastric mammals. To facilitate the digestion of grasses and complex carbohydrates characteristic of the mature ruminant diet, the rumen, reticulum, and omasum must increase in size and capacity to house the symbiotic microbiota until the development of these organs is completed after weaning . BesidesRumen development is an essential factor regulating early solid feed intake and fundamentally affects on cattle’s growth performance and feed efficiency. Diet composition represents one of the most critical factors affecting the establishment of a viable rumen microbiota and, subsequently, fermentation, rumen development, and host production performance ,9. In thTranscriptional reprogramming refers to the phenomenon of global shifts in gene expression typically initiated by transcription factors. During transcriptional reprogramming, the expression of specific genes is elevated, whereas other genes are repressed, compared to the previous state . ReprogrThe downstream gene expression activities activated by developmental transition remain largely unknown. Particularly, system-wide analysis of the underlying dynamics of the transcriptome changes is lacking. We reported earlier using microarray to identify genes differentially expressed between the pre-ruminant and ruminant stages of differentiation induced by diet. The objects of the original study were to identify genes and gene networks contributing to rumen growth and development targeted the mechanisms regulating these processes to improve weaning strategies for young calves . However2 concrete pens with a rubber mat as a bedding surface with no bedding material to avoid confounding dietary treatments if consumed by calves. As illustrated in n = 3) and at six weeks of milk replacer only feeding  to represent two stages of pre-ruminant development. Among the MR + H and MR + G groups, calves were euthanized after 2 weeks (n = 3 per diet) or 4 weeks (n = 3 per diet) of access to solid feed to represent development at two stages of weaning on either a grain-based (MR + G 8w and MR + G 10w) or hay-based (MR + H 8w and MR + H 10w) diet [Animals and tissue collection were described in our previous report . Briefly0w) diet . The rumen tissue was taken from the ventral sac below the cranial pillar, which in a ruminant is consistently exposed to rumen liquor and sometimes the mat during contractions. There are distinct visual cues present to ensure the tissue was predominately exposed to rumen liquor prior to slaughter. The collected rumen tissues were rinsed with tap water, followed by rinsing in ice-cold physiological saline. According to manufacturer instructions, subsamples (~600 mg) of epithelial tissue were fixed in RNAlater  RNA stabilization solution according to manufacturer instructions and stored at −80 °C until RNA extraction. The RNA extraction procedure was reported previously . Brieflyp-value of false discovery rate (FDR) were less than 0.05. Thus, genes that contributed most to separate different cell groups were determined. Venn diagram was performed using jvenn, an interactive Venn diagram viewer [After quality control procedures, RNA was sequenced at 150-bp/paired-end sequence reads using RNA-sequencing service supplied by Novogene Corporation, Inc. . The CLC Genomics Workbench  was used for further RNA-Seq data analysis. Trimmed reads were aligned to the newest bovine reference genome assembly (ARS-UCD1.2) . Gene exm viewer .CLC Genome workbench (Qiagen) was also used for Principal Component Analysis (PCA). PCA was used to finds patterns about whether the samples come from different treatment groups or have phenotypic differences in this study. PCA was performed using all expressed genes. PCA simplifies the complexity in high-dimensional data while retaining trends and patterns. It does this by transforming the data into fewer dimensions, which act as summaries of features. High-dimensional data are very common in biology and arise when multiple features, such as the expression of many genes, are measured for each sample . The goaRNA sequencing statistics are listed in The transcriptome atlas provides the number of transcripts expressed for individual genes before and after weaning and the quantity of transcript expression for individual feeding schemes . We estimated overall weaning, stage-specific diversity by comparing mRNA populations using PCA and a hierarchical heatmap   . The GO All related GO terms were enriched after weaning, indicating transcriptional reprogramming of rumen epithelial tissue induced by the weaning process. As indicated by GO terms, significantly activated biological functions in the ruminal epithelium were predominant metabolic functions. The results indicate critical nutrition-gene interactions occurring during the dietary shift from liquid to solid feeds, which prompted transcriptional reprogramming in rumen epithelial tissue during the developmental progression of ruminant digestion.From comparisons of individual temporal groups and feeding schemes  with the MRO 2w group, we used datasets of identified DEGs to separate the likely affected canonical pathways, cellular functions, upstream regulators, and transcription factor (TF) families regulating the observed temporal gene expression patterns both unique and shared among gene expression patterns during the weaning transition. The putative impact of this developmental shift of gene expression also was realized in the canonical pathway analysis and upstream regulator analysis . Canonic(p = 1.12 × 10−29 of overlap). The mechanistic network contains 462 downstream genes and 19 regulators in the dataset . The transition profoundly impacts transcriptome atlas present in the rumen epithelium as the developmental status dictates differential function. The change in expression of metabolism-related genes is positively correlated with dry matter intake, indicating that the enhanced metabolic process may promote rumen development during weaning . Integratrans differentiation of hepatic stellate cells into myofibroblasts [The transcription factor E2F1 modulates the expression of specific chromatin components in oligodendrocyte progenitor cells during the transition from proliferation to differentiation. Specifically, E2F1 targets cell cycle genes and chromatin components, including those modulating DNA methylation . In our roblasts . Like throblasts . The transcriptome defines ruminal development status and regulates the transition necessary for ruminal development. We observed reprogramming of the transcriptome in the present study, resulting in changes in gene expression, canonical pathways, and cellular functions. Besides, upstream regulators, majorly transcription factors, were demonstrably enriched or activated post-weaning. We can assume that the maturation of rumen epithelium is mediated by transcriptional reprogramming in response to establishing a viable microbiota and its generation of VFAs, likely butyrate . Understanding the processes at a transcriptional reprogramming level will undoubtedly help us understand how cellular metabolism changes related to gene regulation. The gene expression profile of the rumen epithelium has been used to understand molecular changes during weaning ,37 or inInterestingly, as discussed earlier, these same metabolites potentially regulate various physiological functions of the rumen ,41. VFAsPPARA was upregulated and activated after weaning in the current study. It has been well documented that PPARα binds and is activated by numerous fatty acids and fatty acid-derived compounds [PPARA gene product is a ligand-activated transcription factor involved in regulating various processes, ranging from inflammation and immunity to nutrient metabolism and energy homeostasis [Confirming our earlier findings ,45, and ompounds ,32. The eostasis . PPARα geostasis . Likewiseostasis . Our fineostasis . This maeostasis .Another upstream regulator, PPARGC1A, exhibits a high activation post-weaning with a greater activation Z-score in the hay groups than those fed with grain. PPARGC1A, the protein  encoded by this gene, is a transcriptional coactivator that regulates the genes involved in energy metabolism. This protein interacts with PPAR gamma, which permits the interaction with multiple transcription factors . FurtherThe e1F2 signaling pathway showed significantly upregulated activation at the late stage (10 weeks of age) of weaning. eIF2 is an essential factor for protein synthesis that forms a ternary complex (TC) with GTP and the initiator Met-tRNA. After its formation, the TC binds the 40S ribosomal subunit to form the 43S preinitiation complex. eIF2 plays a central role in maintaining a rate-limiting step in mRNA translation . The e1FTGFB1 mRNA expression increased with rumen development during weaning. Likewise, a microarray study by Kim et al. [Reduced activities in upstream regulators such as TGFB1, RICTOR, CLPP, MAP4K4, KDM5A, CCR2, and SRF were observed, corresponding to known or expected developmental changes ruminal tissue during weaning. For example, previous microarray analyses of tissues from the same study suggested a role of TGFB1 in rumen epithelial cell proliferation and differentiation . Specifim et al.  identifim et al. , we idenm et al. . TherefoOf interest, KDM5A, a histone demethylase, was deactivated and played an essential role in blocking p53 signaling to reduce the activity of genes involved in translation initiation . It alsoIntegrative analysis of transcriptome reveals the stimulated biosynthesis of purine nucleotide, purine ribonucleotide, and nucleoside triphosphate as the combined effects of upstream regulators and downstream genes in the weaning group. Nucleic acids are important intracellular signaling molecules and coenzymes, the single most important means of coupling endergonic to exergonic reactions. Nucleic acids also store genetic information in DNA and RNA, chains of nucleotides made through DNA replication and transcription processes. Nucleoside triphosphates also serve as a source of energy for cellular reactions. Given their importance in the cell, the synthesis and degradation of nucleoside triphosphates are under tight control . MoreoveOur data indicated that MR+ G groups had delayed response in transcriptomic reprogramming during the transition, likely reflecting the continued reliance on post-ruminal absorption of energy as grains are acid hydrolyzed during the development of the microbiota in the rumen. This was reflected in the lower number of genes differentially expressed compared to the hay-fed groups. In mature dairy cows feeding of high grain diets results in lowered pH and ruminal dysbiosis, characterized by changes in absorption dynamics of VFAs across the reticulorumen wall, epithelial function, and the epithelial bacteria community structure. Thus, the regulatory pathways affecting altered rumen epithelial gene expression during the weaning process may be linked to well-documented ruminal acidosis symptoms, such as epithelial permeability, inflammation, and proliferation ,61. ConsShifts in gene expression have consisted of transcriptomic reprogramming of the rumen’s epithelial lining to promote and enable the developmental processes and support the maintenance of a functional mature organ. The conversion from reliance on glucose from milk to the use of microbial-fermentation end-products requires a complex transcriptional reprogramming of rumen epithelial tissue, and this reprogramming is driven by characterizing nutrient-gene interactions.


Promyelocytic leukemia nuclear bodies (PML NBs) are multi-protein assemblies representing distinct sub-nuclear structures. As phase-separated molecular condensates, PML NBs exhibit liquid droplet-like consistency. A key organizer of the assembly and dynamics of PML NBs is the ubiquitin-like SUMO modification system. SUMO is covalently attached to PML and other core components of PML NBs thereby exhibiting a glue-like function by providing multivalent interactions with proteins containing SUMO interacting motifs (SIMs). PML NBs serve as the catalytic center for nuclear SUMOylation and SUMO-SIM interactions are essential for protein assembly within these structures. Importantly, however, formation of SUMO chains on PML and other PML NB-associated proteins triggers ubiquitylation and proteasomal degradation which coincide with disruption of these nuclear condensates. To date, a plethora of nuclear activities such as transcriptional and post-transcriptional regulation of gene expression, apoptosis, senescence, cell cycle control, DNA damage response, and DNA replication have been associated with PML NBs. Not surprisingly, therefore, SUMO-dependent PML NB integrity has been implicated in regulating many physiological processes including tumor suppression, metabolism, drug-resistance, development, cellular stemness, and anti-pathogen immune response. The interplay between PML NBs and viral infection is multifaceted. As a part of the cellular antiviral defense strategy, PML NB components are crucial restriction factors for many viruses and a mutual positive correlation has been found to exist between PML NBs and the interferon response. Viruses, in turn, have developed counterstrategies for disarming PML NB associated immune defense measures. On the other end of the spectrum, certain viruses are known to usurp specific PML NB components for successful replication and disruption of these sub-nuclear foci has recently been linked to the stimulation rather than curtailment of antiviral gene repertoire. Importantly, the ability of invading virions to manipulate the host SUMO modification machinery is essential for this interplay between PML NB integrity and viruses. Moreover, compelling evidence is emerging in favor of bacterial pathogens to negotiate with the SUMO system thereby modulating PML NB-directed intrinsic and innate immunity. In the current context, we will present an updated account of the dynamic intricacies between cellular PML NBs as the nuclear SUMO modification hotspots and immune regulatory mechanisms in response to viral and bacterial pathogens. Promyelocytic leukemia nuclear bodies (PML NBs) are ubiquitous, multi-molecular protein condensates associated with the nuclear matrix . By immuPromyelocytic leukemia protein constitutes the primary structural scaffold for PML NBs . The bioSmall ubiquitin-related modifier proteins are covalently conjugated to their target proteins at lysine (K) residues . In humain vitro biophysical and biochemical data now underscore this concept by demonstrating that the accumulation of polySUMO-polySIM polymers results in formation of droplet-like structures and also allows interactions with SUMO/SIM-containing clients depending upon their valency  shift the equilibrium of intra-nuclear PML distribution toward the insoluble matrix-associated fraction leading to increased size and number of PML NBs. Importantly, phosphorylation and SUMOylation of PML have been shown to be involved in this dynamic shift in the equilibrium as As2O3 treatment resulted in an enrichment of the phosphorylated pool of PML leading to its recruitment to PML NBs and an increase of PML SUMOylation  and a gamma activated site (GAS) consensus sequence, explaining induction of PML transcription following IFN stimulation -inducible  by host cellular pattern recognition receptors (PRRs). The subsequent signal amplification step culminates in the transcriptional upregulation of many IFN stimulated genes (ISGs) through Janus kinase (JAK)-Signal transducer and activator of transcription (STAT) signaling pathway . Importamulation . Notablye II IFN . Moreoven of PML . IFN regN itself . The SP1nducible . Interesnducible . IFN-depnducible . IFN stinducible . Anothernscripts .–/– mouse embryonic fibroblasts (MEFs) were less efficient in IFNγ-mediated STAT1 DNA-binding activity compared to wild-type MEFs  genes is crucial for switching the viral infection cycle toward lytic proliferation. Major HCMV IE genes are transcribed under the control of the major immediate early promoter (MIEP), which is only transactivated by a viral protein residing within the tegument layer of infectious virions.Dynamic SUMO modifications have been reported to contribute to the regulations of intrinsic and innate immune defenses against infection with HCMV. The initial observation that herpesviral DNA associates with PML NBs upon its nuclear entry led to the hypothesis that these condensates are usurped by cytomegalovirus and other herpesviruses for productive initiation of the viral IE gene expression . Subsequ+ hematopoietic progenitor cells (HPCs) and monocytes, pp71 remains trapped in cytoplasmic endosomes  protein and the major immediate-early protein IE1, which can affect the integrity of PML NBs . The mecndosomes . As a rendosomes . Importandosomes , substanndosomes . SUMOylandosomes . This lendosomes  and effide novo lytic infection is well studied, importance of pp71 in mediating viral rejuvenation from latency and its role of NB remodeling in this process remains questionable    and is eor pp71) . LUNA haor pp71)  by triggor pp71) . Mechanior pp71) . Substitor pp71) .de novo synthesized IE1 protein to promote prolonged lytic phase gene expression . HHV-6 infects peripheral blood mononuclear cells (PBMCs) and various T-cell lines where it can either establish latent infection or can replicate as a part of its lytic programme. Notably, HHV6 integrates its genome into the telomeric regions of host chromosomes for prolonged maintenance. Importantly, PML NBs and the SUMO machinery were shown to be involved in controlling viral latency as well as viral integration. In case of HHV6A, it was demonstrated that knocking down components of PML NB such as PML, Daxx, and Sp100 significantly increased viral lytic replication and late gene expression. Consistently, progressive lytic infection was found to reduce the number of PML NBs within infected cells with concomitant increase in the puncta size without triggering complete disassembly of these speckled structures . These fWork on HHV-6B has recently revealed a surprising facet of PML and the SUMO machinery in integrating the HHV-6B genome into the telomeric regions of host chromosomes for prolonged maintenance . Furtherin vitro and in vivo . LANA2 promotes PML SUMOylation and induces proteolytic ubiquitylation followed by proteasomal demise of SUMO-enriched PML, again leading to dissolution of PML NBs , 2011. MEpstein-Barr virus, a gammaherpesvirus with a double stranded DNA genome, can cause B cell lymphoma, nasopharyngeal cancer, Hodgkin’s and non-Hodgkin’s lymphomas, and a subset of gastric cancers. It can either be maintained in a latent state and lead to unrestricted cell proliferation and tumorigenesis or can switch to lytic proliferation, especially in the infected epithelial cells. Interestingly, the SUMO system may be involved in maintenance of EBV latent infection. The primary EBV oncoprotein latent membrane protein 1 (LMP1), which is pivotal in modulating viral quiescence, interacts with Ubc9 leading to SUMOylation of many host proteins . Two impThe EBV tegument protein BNRF1 can target PML NBs by interacting with Daxx and disrupting the formation of the Daxx-ATRX Histone H3.3 chaperone complex . MechaniDisruption of the integrity of PML NBs is crucial for lytic rejuvenation of EBV . The EBVAn immediate-early protein of EBV Zta (BZLF1), which is involved in lytic replication of the virus and transactivation of EBV early genes, can also disrupt PML NBs even under exogenously expressed condition . Zta itsThere are also reports of viral protein such as the EBV-encoded protein kinase (EBV-PK), and host regulatory protein such as the cellular scaffolding protein RanBPM to dictate Zta SUMOylation status and therefore to influence Zta-mediated lytic reactivation of EBV . WhetherTherefore, in general, herpesviruses exploit the molecular assembly within PML NBs to heterochromatinize their genome and to go into the latent phase of infection. During rejuvenation, they actively disrupt PML NB integrity by specific lytic proteins to trigger lytic proliferation.In contrast to the early recruitment of herpesviral DNA to PML NBs, adenoviral DNA is associated with PML NBs at a relatively late stage of infection (≥4 h) . InteresInterestingly, the E4orf3-positive tracks reside in close spatial proximity of the adenoviral replication centers (RCs) and a recent report has unveiled the pivotal role of SUMOylation for this positioning . In partApart from E4orf3, E1B-55K also exploits the SUMO system to target host cell proteins. E1B-55K itself is modified by SUMO and the modification facilitates its nuclear retention by blocking a CRM-dependent nuclear export signal . FurtherThe adenoviral protein E1A also has PML NB destabilizing properties . The mecTherefore, HAdV selectively usurps certain components of PML NB components at the expense of antagonizing others to favor its own perpetuation.Chicken embryo lethal orphan adenovirus adopts a robust SUMO-dependent mechanism of PML NB disruption. The viral early protein Gam1 induces ubiquitin-proteasome-dependent degradation of the dimeric SUMO activating enzyme SAE1/SAE2  by recruPapillomaviridae family, possess limited arsenal to counteract host immune responses because of their small genome size and therefore employ a fundamentally different strategy to manipulate with the PML NBs. Unlike other viruses where PML NBs are associated with restrictive chromatin environment and curtailment of viral lytic gene expression and lytic proliferation, HPVs exploit PML NBs for replication. Accordingly, HPV pseudoviruses are more potent in infecting PML expressing cells than PML depleted cells , are formed by homo-multimerization of PML proteins through the RBCC/TRIM motif. These cytosolic PML condensates which even persist in the cytosol after completion of mitosis and nuclear envelope reformation, lack typical PML NB components. When PML translocates back to the daughter cell nuclei, canonical nuclear PML NBs comprising of SUMOylated PML and NB clients are reassembled . NotablyThe mechanism of how HPV L2 protein fosters association of the HPV genome with PML NBs is still poorly understood, but SUMO-dependent regulation appears to be involved in this process. L2 protein itself contains one SUMO conjugation motif at K35 which was evidenced to modulate viral capsid assembly , but itsInterestingly, unlike PML, Sp100 has been observed to act as a restriction factor for HPV transcription and replication but to be unimportant for the maintenance phase of the HPV life cycle , 2017. CPicornaviridae can cause neurological and reproductive complicacies in many mammals, likely including humans through zoonosis. Interestingly, primary fibroblasts derived from PML knockout mice are more vulnerable to infection with EMCV, suggesting that the PML protein might act as a restriction factor for EMCV replication  protease 3C. EMCV which belongs to the family lication . Moreovelication ; PML SIMlication . Unlike lication , therebylication . Consistlication .Picornaviridae family member etiologically responsible for paralytic poliomyelitis. The mechanism includes virus-mediated activation of the extracellular-signal-regulated kinase (ERK), which phosphorylates PML, thereby facilitating PML SUMOylation and translocation to the nuclear matrix. Subsequently, p53 gets recruited to PML NBs and becomes phosphorylated on Ser15 in a PML-dependent way  and pneumolysin ] were also evidenced to induce PML deSUMOylation and multimerization  which triggered a proteasome-dependent Ubc9 destabilization (Shigella to enter cultured epithelial cells. Corroborative in vivo data in an infection model of haploinsufficient Ubc9+/– mice also showed profound destruction of colonic tissue, increased intestinal permeability, and increased signatures of pro-inflammatory cytokines in comparison to wild type controls, suggesting SUMO response to curtail Shigella infection at multiple steps (Shigella infection to be associated with the SUMO-2 modification of multiple transcriptional regulators which control inflammatory response (Alteration in the SUMOylation landscape is also reported in response to bacterial infection, indicating a broader implication of SUMO proteins in controlling infection and immunity. PML knockout mice have been found to be more sensitive to infection by teriosis . A subsenfection . The pornfection . One of nfection . Impairmn of PML  which gen of PML . Antibacn of PML . In contn of PML . One of n of PML . These rrization . Moreoverization . StrikinOylation . The redOylation . In caseO enzyme . The resla entry . Moreovelization , 4. Whetlization . Not surle steps . Indeed,response .Shigella (de novo PML body nucleation from soluble PML. Shigella infection also triggered alteration in the SUMO1 localization and abundance. In cells infected with wild-type Shigella, SUMO1 was visualized as more condensed puncta with sharper edges and brighter staining in comparison to cells that were uninfected or infected with non-invasive Shigella. However, no correlation was found between PML body number and the condensed SUMO1 phenotype (Notably, the number of PML NBs increases during infection with Shigella . Howeverhenotype . Thus, mPromyelocytic leukemia NBs have been emerging to be sub-nuclear niches where SUMO-SIM interactions guide the assembly of a heterogeneous macromolecular complex. The formation involves liquid-liquid phase separation in matrix-associated spherical condensates but allows a dynamic equilibrium with the surrounding nucleoplasmic contents. With the growing list of client proteins which are shown to be transiently associated with PML NBs , functioUP and SM wrote the manuscript. UP prepared the figures. Both authors approved the final version of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Adenosine is frequently used for paroxysmal supraventricular tachycardia (PSVT) treatment in the emergency department (ED). Atrial and ventricular pro-arrhythmic effects of adenosine were described in the literature, but ventricular fibrillation (VF) secondary to adenosine administration was rarely reported (with an incidence of < 1%). Reported herein is the first case of a 72-year-old female patient who developed VF hemodynamic collapse after an intravenous administration of adenosine for PSVT treatment. She had no known pre-excitation or accessory pathway, nor any underlying structural heart disease or prolonged QT syndrome. Raising awareness of this potential life-threatening pro-arrhythmic effect of adenosine is important, given its frequent use for PSVT treatment in the ED. Adenosine blocks the AV nodal conduction and increases the AV nodal refractory period, thereby interrupting the re-entry pathway through the AV node, resulting in AVNRT termination.3Paroxysmal supraventricular tachycardia (PSVT) refers to any tachydysrhythmia arising from above the level of the Bundle of His and encompasses atrioventricular re-entrant tachycardia (AVRT) and atrioventricular nodal re-entry tachycardia (AVNRT). AVNRT is the most common cause of palpitations in patients with a structurally normal heart, which involves an anatomical re-entry circuit within the AV node. Vagal maneuvers aid in conversion to sinus rhythm, and the modified Valsalva maneuver effectiveness was well documented in both the pre-hospital and hospital settings compared to that of the traditional method.A 72-year-old female patient presented to the emergency department (ED) after a primary care physician referral for tachycardia, who saw her with complaints of epigastric discomfort, vomiting, and loss of appetite for the past 2 days. An electrocardiogram (ECG) at the clinic revealed a narrow complex tachycardia of 169 beats/min. She was admitted for ischemic stroke 6 months earlier and was on aspirin. During that admission, PSVT developed but was successfully treated with intravenous (IV) adenosine. She was reviewed by the cardiologist, and 2D echocardiography was performed, which did not reveal any underlying structural heart abnormalities. In addition, an electrophysiological study confirmed the underlying etiology of PSVT as AVNRT.On arrival, she was alert with a temperature of 37.3°C; heart rate of 170 beats/min; respiratory rate of 25 cycles/min; blood pressure of 112/81 mm/Hg; and oxygen saturation of 97% on room air. Her physical examination was normal. The ECG revealed a narrow complex tachycardia suggestive of AVNRT due to the presence of retrograde conduction of P waves in leads I and aVR . PreviouVagal maneuver  was attempted without success. A carotid sinus massage was not performed as the patient had a stroke history. IV adenosine at 6 mg was given for pharmacological conversion. Shortly after IV adenosine administration, the patient became unresponsive and developed a generalized tonic-clonic (GTC) seizure. Pulse was absent, and the cardiac monitor revealed ventricular fibrillation (VF). Cardiopulmonary resuscitation was immediately started together with the preparation for defibrillation. However, just before defibrillation, the seizure spontaneously aborted and she had a palpable pulse with a return of spontaneous circulation (ROSC). The whole episode of seizure and VF lasted for approximately 8–10 s. The cardiac monitor revealed a normal sinus rhythm conversion and the patient spontaneously regained consciousness. Repeat vital signs were stable with a heart rate of 72 beats/min; blood pressure of 102/62 mm/Hg, and oxygen saturation of 99% on room air.A rhythm strip  review rBlood investigations were done in the ED upon patient arrival before adenosine administration. These included a complete blood count with hematocrit level, serum electrolytes, and thyroid function test, which all revealed normal results. Coupled with her normal physical examination without signs of dehydration and ECG that was not suggestive of sinus tachycardia, the possibility of dehydration as a contributory factor to the tachycardia was ruled out. The patient was admitted to the High Dependency Unit (HDU) under cardiology. During admission, her serial cardiac enzymes were normal. Her symptoms of epigastric discomfort and vomiting were attributed to gastritis. She had another episode of SVT in the HDU, which was successfully converted with IV diltiazem. Myocardial perfusion imaging was negative for ischemia, and the transthoracic echocardiography revealed a normal ejection fraction without regional wall motion abnormalities. An electrophysiological study was not performed during this admission due to her advanced age and other co-morbidities. She was discharged stable after a few days and was started on long-term oral diltiazem.4Adenosine is indicated for PSVT (AVNRT and orthodromic AVRT) conversion to sinus rhythm. Antidromic AVRT presents as a wide complex QRS tachycardia due to antegrade conduction occurring via the accessory pathway and retrograde conduction via the AV node. The rate is usually 200–300 beats/min and confirmation diagnosis is difficult in the acute setting. Adenosine administration is dangerous in patients with SVT involving an accessory pathway, including Wolff-Parkinson-White syndrome, thus should be avoided.5 Adenosine antagonizes the cyclic adenosine monophosphate-mediated catecholamine stimulation of the ventricular muscle, which explains this form of VT as adenosine-sensitive. However, in patients with known structural heart disease presenting with regular wide complex tachycardia, where re-entry circuit is the most common mechanism for VT manifestation due to abnormal myocardial scarring from prior ischemia or infarction, adenosine is contraindicated as it worsens the arrhythmia and precipitates VF.6Adenosine was studied to effectively cardiovert a subset of idiopathic ventricular tachycardia (VT), particularly the right ventricular outflow tract tachycardia, which is typically catecholamine-induced.7 In these patients, a critical antegrade AV nodal conduction prolongation allowed a retrograde atrial activation via an accessory pathway, causing the emergence of a reciprocating tachycardia. Adenosine-induced ventricular arrhythmias were commonly reported in structurally normal hearts and normal QT intervals.8 These include premature ventricular contractions (PVC) and non-sustained VT, which are clinically insignificant, requiring no intervention. Significant ventricular arrhythmias such as paroxysmal ventricular tachycardia (PVT), torsades de pointes, and VF are more rarely encountered, causing serious adverse outcomes that require advanced life support measures. Non-sustained and sustained torsades de pointes that require cardioversion occurred after adenosine administration for SVT.9 Another case of adenosine-induced VF resulting in a hemodynamic collapse that required defibrillation was reported,10 but the presenting ECG was later reviewed to be atrial fibrillation with rapid ventricular response rather than SVT. Our case is the first report about VF with hemodynamic collapse secondary to adenosine treatment for AVNRT, in the absence of structural heart disease or prolonged QT syndrome.Atrial and ventricular pro-arrhythmic effects of adenosine were described. A paradoxically increased tachycardia, when used in AVNRT, was reported. These patients were found to have dual AV node pathways where adenosine preferentially blocks the fast antegrade pathway, allowing a re-entry circuit to develop. In addition, adenosine was found to increase the ventricular rate when used in orthodromic AVRT.11 A case of adenosine-induced VF was observed as a pause-dependent phenomenon,12 whereby atrioventricular conduction block that resulted in a long sinus pause after an adenosine administration is accompanied by a compensatory response, provoking the re-initiation of tachyarrhythmias in an attempt to maintain cardiac output. In addition, underlying acquired or congenital long QT syndrome precipitate life-threatening bradycardia-induced PVT/VF,13 whereby the slowing of ventricular rate during the adenosine administration results in progressive QT prolongation, which reflects prolonged repolarization and gives rise to early-after depolarization (EAD). These EADs manifest as PVCs and are known as the R on T phenomenon when occurring in the preceding T wave, causing torsades de pointes. Moreover, adenosine causes a reflex increased circulating catecholamine levels and sympathetic nerve traffic by sympathetic stimulation in the carotid body chemoreceptors.14 Catecholamine release causes increased ventricular automaticity as demonstrated in the A2 adenosine receptor in the ventricular myocytes. These mechanisms are responsible for the pro-excitatory effects of adenosine administration in VT/VF development.Several studies outlined the mechanisms behind adenosine-induced atrial and ventricular arrhythmias. Adenosine shortens the effective refractory period in atrial myocytes and predisposes to atrial arrhythmias through increased spatial dispersion of refractoriness.In our patient, a low dose of adenosine at 6 mg induced a malignant ventricular arrhythmia, a rare idiosyncratic response especially in the absence of prolonged QT syndrome and structural heart diseases. Furthermore, the patient had a PSVT history, which was successfully converted to sinus rhythm without complications. This further demonstrates the inherent pro-arrhythmic potential of adenosine when used. The possible mechanism resulting in VF in our case would likely be that of a pause-dependent phenomenon followed by increased catecholamine levels and sympathetic stimulation; provoking the initiation of tachyarrhythmia. The short duration of hemodynamic collapse and ROSC reflects the transient effect on the atrioventricular node and rapid adenosine inactivation in the human plasma by uptake into the erythrocytes and endothelial cells.Adenosine remains a safe and effective agent for PSVT treatment in the ED. Clinicians are well aware of the side effects, such as bronchospasm, chest pain, and bradycardia, but its potential to induce life-threatening tachyarrhythmias are rare, albeit transient in nature owing to its short duration of action. Therefore, during adenosine administration, the emergency physician must bear in mind the possibility of cardiovascular collapse from malignant arrhythmias. All patients must be placed on continuous cardiac monitoring during cardioversion and prompt access to resuscitation and defibrillation equipment must be ensured.NilNilNilAll the authors have no potential conflict of interestShu Yu Lee is responsible for manuscript preparation, literature search, and drafting of the initial manuscript. Sohil Pothiawala and Chong Meng Seet reviewed and edited the manuscript, followed by final approval of the manuscript for submission.All authors have read and approved the final draft of the manuscript.


Network nodes were defined by brain parcellation using the Schaefer atlas, while connectivity strength between two nodes was determined by comparing the distribution of PET uptake values within each node using a Kullback–Leibler divergence similarity estimation (KLSE). After constructing individual brain networks, a linear and quadratic regression analysis of metabolic connectivity strengths within- and between-networks was performed to model age-dependency. In addition, the age dependency of metrics for network integration (characteristic path length), segregation , and centrality (number of hubs) was assessed within the whole brain and within predefined functional subnetworks. Overall, a decrease of metabolic connectivity strength with healthy aging was found within the whole-brain network and several subnetworks except within the somatomotor, limbic, and visual network. The same decrease of metabolic connectivity was found between several networks across the whole-brain network and the functional subnetworks. In terms of network topology, a less integrated and less segregated network was observed with aging, while the distribution and the number of hubs did not change with aging, suggesting that brain metabolic networks are not reorganized during the adult lifespan. In conclusion, using an individual brain metabolic network approach, a decrease in metabolic connectivity strength was observed with healthy aging, both within the whole brain and within several predefined networks. These findings can be used in a diagnostic setting to differentiate between age-related changes in brain metabolic connectivity strength and changes caused by early development of neurodegeneration.Contrary to group-based brain connectivity analyses, the aim of this study was to construct individual brain metabolic networks to determine age-related effects on brain metabolic connectivity. Static 40–60 min [ Many studies have shown a progressive decrease of cerebral [18F]FDG uptake with aging, mainly observed in the medial frontal lobe and anterior cingulate cortex  were recruited prospectively between December 2015 and February 2017. The main exclusion criteria for this study were major internal pathology or having (had) cancer, having a first-degree relative with dementia, a history of important neurological and/or psychiatric disorders, and substance abuse or current use of centrally acting medication. Subjects underwent a neurological examination resulting in a Mini-Mental State Examination (MMSE) score ≥ 28 and a score of ≤9 on the Beck’s Depression Inventory (BDI) for all subjects. This study was approved by the local ethics committee of UZ Leuven Gasthuisberg, and all participants gave written informed consent.18F]FDG (152 ± 10 MBq) and underwent a simultaneous [18F]FDG PET-MR scan . Listmode data acquired between 40 and 60 min were rebinned in four frames of 5 min and corrected for motion. Sinograms were corrected for dead time, random, and scatter, while a proprietary template-based MR-based attenuation correction (MRAC) was used for attenuation correction. Each frame was reconstructed using ordered subset expectation maximization  and included time of flight (TOF) information, resolution modeling, and a Gaussian post-smoothing with a full width half maximum (FWHM) of 4.5 mm. The multi-frame PET data were rescaled to standardized uptake values (SUV) and averaged to obtain a static SUV PET image.Subjects received an intravenous bolus injection of FDG PET images were spatially normalized using a non-linear normalization using the CAT12 toolbox of Statistical Parametric Mapping  and smoothed with a Gaussian filter of 8 mm. For each subject, [18F]FDG uptake was normalized to the total uptake in the GM. Subject specific tissue probability maps for GM, white matter (WM), and cerebrospinal fluid (CSF) were derived based on the 3D T1-weighted MR data in SPM12 and used to delineate volume of interest (VOI) defined by the Schaefer atlas  of intensity values for that parcel. All PDFs were estimated using brain parcels in MNI space containing minimum 800 voxels. Furthermore, the PDF for each parcel was estimated using the kernel density estimation (KDE) with optimal bandwidths for the number of voxels of that specific parcel chosen automatically using the diffusion Botev method as implemented in the KDE-diffusion toolbox in Python version 3.9 (DKL) between two PDFs. However, to have a symmetric measure, the following variation of DKL was used:For depicting an individual metabolic network for each subject, the 100 brain parcels, determined by the Schaefer atlas, were considered as nodes, and the FDG PET. Our results showed that individual brain metabolic networks became less integrated and less segregated during aging. We observed these age-related effects on the level of the whole brain as well as within the functional subnetworks except within the control, limbic, and visual network. The same decrease of metabolic connectivity was found between several networks across the whole-brain network and the functional subnetworks. Meanwhile, no network reorganization was observed with aging as distribution of hubs throughout the brain, and different subnetworks remained unchanged during aging.To our knowledge, this is the first study to explore the effect of age on individual brain metabolic connectivity using [18F]FDG uptake could result in lower correlation measures. In addition, correlation measures are not sensitive to differences in regional uptake values which are consistent across subjects. On the contrary, the KLSE approach compares the intra-regional metabolic distribution between different regions within a single subject where it uses all uptake values within each brain region and thus much more information compared with correlation-based measures which consider only the averaged regional uptake of brain regions. As such, this approach provides a quantitative representation of the tracer distribution throughout the brain and the different subnetworks with a high average metabolic strength between nodes representing a rather homogeneous [18F]FDG uptake in the corresponding brain regions. This way, metabolic connectivity estimated across subjects using correlation measures and with-subject using the KLSE approach proved to be high complementary. Meanwhile, univariate VOI-based and voxelwise approaches have mainly been used so far to study age-related effects on brain glucose metabolism. These studies showed differences in the age-dependency of glucose metabolism between different brain regions with consistently higher age-related decrease of [18F]FDG uptake in the frontal, cingulate, temporal cortex, and in subcortical GM regions compared with other brain regions . KVL has conducted this study as senior clinical research fellow for the Research Foundation Flanders (FWO). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


EVs can provide valuable information on how a pathogen sends messages to other pathogens and hosts . This Research Topic provides an overview of the mechanism of EV-mediated communication between hosts and viruses, parasites, and fungi. This Research Topic consists of 17 papers, including 8 reviews and 9 original papers. Several studies on this topic assessed the effects of EVs on the interactions between pathogens and hosts, and the mechanisms of EV-mediated communication between hosts and pathogens were also addressed.Extracellular vesicles (EVs) isolated from pathogens mediate communication between parasites and their hosts under a variety of physiological and pathological conditions. EVs deliver cell-free messages Duguet et al.). They showed that EVs isolated from Caenorhabditis elegans contain microRNAs and small regulators that affect biological processes and comment on their role in host-nematode communication. Parasite-derived miRNAs regulate host immune system mRNAs.The first original article published in this Frontiers in Cellular and Infection Microbiology Parasite and Host issue is from Duguet’s group  and hydatid cysts release EVs that are exosome-like based on size and morphology. The authors analyzed the miRNA, circRNA, and lncRNA profiles of the 20 most abundant miRNAs in EVs and explored their possible roles in biological processes, especially in pathways associated with pathogenicity and the host immune response. These EVs contain small RNA species, including specific miRNAs that are homologous to host miRNAs and induce immunomodulation in the host.The paper by Cryptococcus deneoformans, a fungus that causes meningoencephalitis in immunocompromised patients. In this study, the authors showed that fungal shedding of EV RNAs and cryptococcal intersectin protein (Cin1) govern a unique Cin1-Wsp1-Cdc42 endocytic pathway required for intracellular transport, virulence, and regulated particle secretion. Cin1 has clinical importance as an exRNA, and studies using cutting-edge technology in cryptococcal pathogenesis may contribute to the discovery of novel therapeutic strategies .Another article discusses the role of Nawaz et al. included proteomic analysis of EVs purified from the saliva of Haemaphysalis longicornis. The bush tick is a vector of human disease-causing agents, such as the agent causing thrombocytopenia syndrome. The authors found that EVs carry proteins that may be helpful during tick development and vesicular proteins involved in proton transport, detoxification, ECM-receptor interaction, ribosomes, RNA transport, ABC transporters, and oxidative phosphorylation.The study by Saini and Rai showed that treatment with linoleic acid (LA) inhibited Leishmania donovani infection in macrophages, suppressed the parasitic load, and reduced the levels of IL-12 and iNOS. LA promoted a protective-type immune response in the infected host and inhibited the release of Leishmania-derived microvesicles. Soares’ team also presented data on macrophage activation using EVs isolated from L. infantum L. braziliensis, and L. amazonensis. EVs from L. braziliensis and L. infantum parasites failed to induce a proinflammatory response. EVs from both the L. infantum WT and LPG-deficient mutant (LPG-KO) did not show any differences in their interactions with macrophages, suggesting that LPG alone was not sufficient for activation . Another group investigated whether Leishmania amazonensis or EVs modulate B-1 cell activation and differentiation. L. amazonensis infection in B-1 cells decreased the production of NO and ROS. TLR-2, TLR-6 and TLR-9 had significantly higher expression in B-1 cells from mice intraperitoneally injected or stimulated with EVs .Several studies on this topic have assessed the role of EV release in leishmaniasis. Gualdrón-López et al. discussed multiparameter flow cytometry combined with cell and EV purification techniques to determine and investigate the interactions of plasma-derived EVs from human spleen cells from Plasmodium vivax-infected patients (PvEVs). They used size-exclusion chromatography (SEC) to separate EVs from the bulk of the soluble plasma proteins and stained isolated EVs with fluorescent lipophilic dyes .Lim et al.). Another review discussed EVs containing infective viral genomes that are secreted into the extracellular space (Martins and Alves). EVs can trigger antiviral responses and cytokine secretion even in uninfected cells near the infection, and the role of EVs during viral infections is crucial for comprehending viral mechanisms and how to respond to emerging viral diseases (Martins and Alves). In this review, the symbiosis between the TV-specific endosymbiont viruses Trichomonasvirus and Trichomonas vaginalis was studied by exploiting sEVs as a vehicle for intercellular communications and by modifying their protein cargo to suppress host immune activation, including NF-κB activation and increases in IL-8 and RANTES. The virus may offer evolutionary benefits to its protozoan host, at least partially, by altering the immunomodulatory properties of EVs spreading from the site of infection to noninfected immune effector cells. EVs serve as vehicles for intercellular communication and modify their protein cargo to suppress host immune activation .This Research Topic also includes reviews that discuss the role of EVs in viral infections. Dr. Soekmadji’s group discussed the role of EVs in hepatic fibrosis and how understanding their biological mechanism of action might be beneficial for developing therapeutic strategies to treat chronic liver disease .A review on influenza virus infection discusses the EVs released from infected cells, implying the functional relevance of EVs for influenza virus dissemination, EV-based influenza vaccines, and therapeutic strategies to combat the influenza virus . In parallel, other authors discussed the diverse functions of EVs in fungi, from the regulation of physiological events and responses to specific environmental conditions to the mediation of highly complex interkingdom communications and the function of EVs as vehicles for the delivery of biologically active molecules . Protozoan EV reviews showed that the EVs isolated from pathogenic protozoa are disseminated alongside their biomolecules, and there are specific immune cell responses to protozoan parasite-derived EVs. Protozoan-host interactions release EVs that are crucial for the immunomodulatory events triggered by parasites . Additionally, EVs from these organisms have a role in the digestive tracts of invertebrate hosts prior to parasite transmission. This review summarizes the available data on how EVs from medically important trypanosomatids affect parasite interactions with vertebrate and invertebrate hosts . Schistosomes release EVs that modulate the host immune response and EV-harbored miRNAs to upregulate the innate immune response of the M1 pathway and downregulate differentiation towards adaptive Th2 immunity. EVs may facilitate the development of novel tools for diagnostics and deliver therapy in relation to schistosomiasis, as well as to immune-associated disorders (Avni and Avni).Another review shows how cross-kingdom sRNA trafficking occurs in EVs participating in sRNA delivery in the host during infection, as well as the production of EVs by bacterial and fungal pathogens that help establish the disease. Bacterial vesicle RNA cargo plays roles in recipient host cells by regulating gene expression and modulating the immune response. In fungi, the RNA molecules present in EVs are diverse and participate in communication between the host and pathogenic fungi  number 2019/15909-0 and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) grant 408186/2018-6 and FAPESP 2020/07870-4 (ACT).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


A new study in PLOS Biology uses artificial intelligence (AI) to accurately predict Km on a proteome-wide scale, paving the way for dynamic, genome-wide modeling of metabolism.Michaelis constants (K The Michaelis–Menten equation was derived by Leonor Michaelis and Maud Menten to quantify the velocity of an enzymatic reaction using measurable concentrations of enzyme and substrate even before the exact nature of enzymes was elucidated  1]. Des. Des1]. m) in the equation is a pseudo-equilibrium constant that corresponds to the substrate concentration at which an enzyme operates at half of its maximum catalytic rate  ieactions  3]. For. Form) ibstrates [3]. In tPLOS Biology by Kroll and colleagues uses AI to predict Km purely from protein and substrate information [Artificial intelligence (AI), empowered by the increasing availability of Big Data, is transforming many aspects of our lives and multiple research fields . Rooted ormation . Their gm values from public databases to train AI models with an increasing amount of additional substrate and protein information [m values only deviated from experimental values by 4-fold on average. However, model performance was still increasing with the size of the training dataset, and, therefore, it will be important to continue improving the model as more experimental data become available, particularly regarding extreme values poorly represented in public datasets. Overall, Kroll and colleagues provide a very significant step forward that outperforms previous attempts at predicting Km.The authors used Kormation . First, ormation . The autm predictions for 47 model organisms. We foresee that these invaluable predictions will open new avenues of research in multiple fields. In particular, we think they could be an important step toward dynamic, genome-scale metabolic models (GSMMs). GSMMs emerged in the last decade as powerful constraint-based modeling platforms to achieve quantitative predictions of metabolic fluxes through multiomics data integration [m predictions proteome-wide by Kroll and colleagues could fuel a new generation of GSMMs that accurately predict dynamic metabolic flux maps to uncover new drug targets and boost our ability to quantitatively and accurately model metabolism.Importantly, the authors not only provide the code in a public repository, but they also make available genome-scale Kegration . GSMMs hegration ,10, but


In separate groups of animals, in vivo laser Doppler flowmetry was used to measure relative CBF changes over a range of BP using phlebotomy and the pressor phenylephrine to lower and raise BP, respectively. Absolute CBF measurements from microspheres were then used to calibrate laser Doppler measurements to calculate the relationship between CBF and BP, i.e., “cerebral autoregulation curves.” Un-operated and sham-operated groups exhibited similar cerebral autoregulatory curves, showing comparable levels of relatively constant CBF over a range of BP from ~80 mmHg to ~130 mmHg. In contrast, SAH animals exhibited a narrower autoregulatory range of BP, which was primarily due to a decrease in the upper limit of BP whereby cerebral autoregulation was maintained. Importantly, SAH animals also exhibited a marked decrease in CBF throughout the entire range of BP. In sum, this study provides evidence of the dramatic reduction in cortical CBF and the diminished range of autoregulation after SAH. Furthermore, this novel methodology should pave the way for future studies examining pathological mechanisms and/or therapeutic strategies targeting impaired cerebral autoregulation, a pathology common to many cardiovascular and cerebrovascular disorders.Subarachnoid hemorrhage (SAH) is a common form of hemorrhagic stroke associated with high rates of mortality and severe disability. SAH patients often develop severe neurological deficits days after ictus, events attributed to a phenomenon referred to as delayed cerebral ischemia (DCI). Recent studies indicate that SAH-induced DCI results from a multitude of cerebral circulatory disturbances including cerebral autoregulation malfunction. Cerebral autoregulation incorporates the influence of blood pressure (BP) on arterial diameter in the homeostatic regulation of cerebral blood flow (CBF), which is necessary for maintaining constant brain perfusion during physiological swings in systemic BP. In this study, we quantitatively examined the impact of SAH on cerebral autoregulation using a mouse endovascular perforation model and a newly developed approach combining absolute and relative CBF measurements. This method enables a direct quantitative comparison of cerebral autoregulation between individual animals , which cannot be done solely using relative CBF changes by laser Doppler flowmetry. Here, absolute CBF was measured  Subarachnoid hemorrhage (SAH), a devastating form of hemorrhagic stroke caused by cerebral aneurysm rupture , occurs via enhanced constriction in response to increases in systemic blood pressure and conversely dilate promoting enhanced blood flow when blood pressure drops. Since the initial report by Bayliss, the molecular mechanisms underlying myogenic tone have been extensively studied. Although the identity of pressure-sensing molecules within the vascular wall is still debated , maintaining relatively constant brain perfusion in the face of continual physiological fluctuations in systemic blood pressure . This ph debated , the linablished .Pressure-induced cerebral vasoconstriction is altered in a variety of pathological conditions. For example, cerebral artery myogenic tone is attenuated in animals with aging , ischemiThis study aimed to elucidate the impact of SAH on cerebral autoregulation using an endovascular perforation SAH model in mice. Previous studies  have evaSAH was induced in 3–5-month-old male C57BL/6 mice (The Jackson Laboratory) using an endovascular perforation model as previously described ,b. BriefThe relationship between relative changes in CBF and systemic blood pressure was evaluated under the combined anesthesia of urethane  and α-chloralose . The use of urethane and α-chloralose as anesthetic agents has previously been shown to have a minimum effect on CBF and cerebral autoregulation in mice . As intr6 microspheres suspended 0.1 ml saline, Invitrogen) were injected through the left ventricle of the heart, and a reference blood sample (~0.1 ml) was collected from a femoral artery cannula 1 min after microsphere injection. Animals were then immediately decapitated, and tissues collected, weighed, and stored at −80°C until assayed. Following previously established procedures (™ H4 Hybrid Multi-Mode Microplate Reader (BioTek). Tissue blood flow was calculated using the following equation: Blood flow (ml/100 g tissue/min) = [(Fluorescent intensity in tissue/Fluorescent intensity in reference blood) × blood sampling rate (ml/min)] × 100/tissue weight (g) as shown by Tissue perfusion in the ipsilateral and contralateral cerebral cortex, cerebellum, spleen, and kidney was quantified in separate groups of animals using fluorescently tagged microspheres . In brieocedures , tissuesFluorescence-tagged microspheres were purchased from Invitrogen (cat# F8844). All other chemicals and reagents were obtained from Sigma-Aldrich.p < 0.05 was considered statistically significant.Data are presented as mean ± standard error of the mean. Statistical analysis was accomplished by GraphPad Prism 8 software using one-way ANOVA followed by Tukey’s multiple comparisons test (Tukey’s). 2, pCO2, and pH were not different between treatment groups (n = 7) compared to control  and sham-operated animals  vs. control  and sham-operated animals . Considering that there were no differences in the wet weight of brain tissue among groups  in the sham-operated group, which was not statistically different compared to the control group. These results demonstrate an approach enabling comparisons of MAP vs. CBF relationships between groups of animals and that the sham-operation procedures performed in this study do not impact cerebral autoregulation.Cerebral autoregulation  or the avia endovascular perforation at the Circle of Willis. CBF was dramatically decreased in SAH animals across the entire range of blood pressures examined, i.e., between 40 mmHg and 190 mmHg (n = 6) compared to un-operated control and sham-operated animals. Analysis of the MAP-CBF relationship curve indicates that SAH impacts the upper limit , rather than the lower limit , of cerebral autoregulation  and underscore the value of quantitative approaches that enable evaluation of the relationship between systemic blood pressure and CBF.For CBF quantification, we adapted fluorescent microsphere methodology widely used in rats . Consistex vivo studies using isolated cerebral arteries demonstrate a phenomenon referred to as “forced dilatation,” where active vasoconstriction is progressively lost at intravascular pressures exceeding ≈140 mmHg (Interestingly, we still observed cerebral autoregulation in SAH animals, despite decreased CBF over the physiological range of blood pressures. Our previous studies using both a rabbit double-injection SAH model  and a ra140 mmHg . With th140 mmHg . Ensuing140 mmHg  and that140 mmHg , and thu140 mmHg . A betteIn conclusion, by developing and applying an approach enabling the quantitative analysis of the relationship between blood pressure and CBF, this study provides valuable insights into the detrimental impact of SAH on cerebral autoregulation. Of import, we demonstrate a downward shift in CBF across the range of autoregulatory blood pressures in SAH mice. Further, the upper blood pressure limit of cerebral autoregulation was reduced in SAH mice compared to sham-operated and un-operated animals. The resulting reduction in CBF combined with a narrower range of cerebral autoregulation likely contributes to DCI after SAH. Moreover, our newly established method of quantitatively analyzing cerebral autoregulation creates a foundation for future studies to examine physiological and pathological mechanisms of cerebral autoregulation in a host of disease states.The original contributions presented in the study are included in the article/The animal study was reviewed and approved by the Institutional Animal Care and Use Committee at the University of Vermont.in vivo and in vitro experiments, and prepared the manuscript. HF supported in vitro procedures of absolute CBF measurement. MN contributed to the research management. GW designed the research and prepared the manuscript. All authors contributed to the article and approved the submitted version.MK designed and directed the research, acquired and analyzed data of The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


At the beginning of the COVID-19 pandemic, consuming media was critical to identify precautionary behaviors to reduce the spread of the virus, particularly for older adults. Media consumption leads to heightened awareness, but may also negatively affect mental health. We examined whether non-social and social media consumption impacted anxiety and depression relative to pre-COVID-19 symptoms. We conducted an anonymous, cross-sectional survey in May and June 2020. Participants , were asked to estimate their amount of time spent consuming pandemic-related media each day, and to report on anxiety and depressive symptoms both before and after the pandemic onset. We characterized change in anxiety and depression by subtracting scores on current anxiety and depressive symptoms from their recalled symptoms prior to the pandemic. Respondents with high pandemic-related media consumption (>3hrs) were more likely to have increased anxiety, compared to those with low (<1hr) media consumption . Similarly, respondents with increased social media consumption during the pandemic were 64% more likely to have depression, compared to those who did not use social media. This association was bi-directional— those who reduced their social media use were 45% less likely to have depression and 26% less likely to have anxiety, compared to those who never used social media. Older adults consuming more pandemic-related media had increased anxiety. Increased social media consumption was associated with elevated depression symptoms. The potential benefits of media consumption about the COVID-19 pandemic may have unintended negative consequences on mental health.