Multivalent Small-Molecule Pan-RAS Inhibitors.

Design of small molecules that disrupt protein-protein interactions, including the interaction of RAS proteins and their effectors, may provide chemical probes and therapeutic agents. We describe here the synthesis and testing of potential small-molecule pan-RAS ligands, which were designed to interact with adjacent sites on the surface of oncogenic KRAS. One compound, termed 3144, was found to bind to RAS proteins using microscale thermophoresis, nuclear magnetic resonance spectroscopy, and isothermal titration calorimetry and to exhibit lethality in cells partially dependent on expression of RAS proteins. This compound was metabolically stable in liver microsomes and displayed anti-tumor activity in xenograft mouse cancer models. These findings suggest that pan-RAS inhibition may be an effective therapeutic strategy for some cancers and that structure-based design of small molecules targeting multiple adjacent sites to create multivalent inhibitors may be effective for some proteins.

Bridging the gap between molecular and genomic epidemiology in tuberculosis: inferring MIRU-VNTR patterns from genomic data.

The transition from MIRU-VNTR-based epidemiology studies in tuberculosis (TB) to genomic epidemiology has transformed how we track transmission. However, short-read sequencing is poor at analyzing repetitive regions such as the MIRU-VNTR loci. This causes a gap between the new genomic data and the large amount of information stored in historical databases. Long-read sequencing could bridge this knowledge gap by allowing analysis of repetitive regions. However, the feasibility of extracting MIRU-VNTRs from long reads and linking them to historical data has not been evaluated. In our study, an in silico arm, consisting of inference of MIRU patterns from long-read sequences (using MIRUReader program), was compared with an experimental arm, involving standard amplification and fragment sizing. We analyzed overall performance on 39 isolates from South Africa and confirmed reproducibility in a sample enriched with 62 clustered cases from Spain. Finally, we ran 25 consecutive incident cases, demonstrating the feasibility of correctly assigning new clustered/orphan cases by linking data inferred from genomic analysis to MIRU-VNTR databases. Of the 3,024 loci analyzed, only 11 discrepancies (0.36%) were found between the two arms: three attributed to experimental error and eight to misassigned alleles from long-read sequencing. A second round of analysis of these discrepancies resulted in agreement between the experimental and in silico arms in all but one locus. Adjusting the MIRUReader program code allowed us to flag potential in silico misassignments due to suboptimal coverage or unfixed double alleles. Our study indicates that long-read sequencing could help address potential chronological and geographical gaps arising from the transition from molecular to genomic epidemiology of tuberculosis. IMPORTANCE: The transition from molecular epidemiology in tuberculosis (TB), based on the analysis of repetitive regions (VNTR-based genotyping), to genomic epidemiology transforms in the precision with which we track transmission. However, short-read sequencing, the most common method for performing genomic analysis, is poor at analyzing repetitive regions. This means that we face a gap between the new genomic data and the large amount of information stored in historical databases, which is also an obstacle to cross-national surveillance involving settings where only molecular data are available. Long-read sequencing could help bridge this knowledge gap by allowing analysis of repetitive regions. Our study demonstrates that MIRU-VNTR patterns can be successfully inferred from long-read sequences, allowing the correct assignment of new cases as clustered/orphan by linking new data extracted from genomic analysis to historical MIRU-VNTR databases. Our data may provide a starting point for bridging the knowledge gap between the molecular and genomic eras in tuberculosis epidemiology.

ENDOLUNG trial. A phase 1/2 study of the Akt/mTOR inhibitor and autophagy inducer Ibrilatazar (ABTL0812) in combination with paclitaxel/carboplatin in patients with advanced/recurrent endometrial cancer.

BACKGROUND: Carboplatin and paclitaxel (CP) have been the standard of care for advanced/recurrent endometrial cancer (EC) for many years. However, this chemotherapy combination shows limited efficacy and recurrences often occur in less than 12 months. ABTL0812 is a novel drug that selectively kill cancer cells by cytotoxic autophagy and has shown anticancer efficacy in preclinical models of EC in combination with CP. METHODS: ENDOLUNG was an open-label, phase 1/2 clinical trial designed to determine the safety and efficacy of Ibrilatazar (ABTL0812) with CP in patients with advanced/recurrent EC and non-irradiable stage III and IV squamous non-small cell lung cancer (sq-NSCLC). The phase 1 part consisted of a 3 + 3 de-escalation design followed by an expansion cohort with 12 patients. The primary endpoint was safety. ABTL0812 starting dose was 1300 mg tid combined with carboplatin at area under the curve (AUC) 5 and paclitaxel at 175 mg/m2 both administered every 21 days for up to 8 cycles. The phase 2 part included a total of 51 patients. The primary endpoint was overall response rate (ORR) and the secondary endpoints included duration of response (DOR), progression-free survival (PFS) and overall survival (OS). RESULTS: During the phase 1 only one dose limiting toxicity (DLT), a grade 4 neutropenia, was observed in 1 out of 6 patients, thus no de-escalation was applied. One additional DLT, a grade 3 febrile neutropenia, was observed in the expansion cohort, thus the recommended phase 2 dose (RP2D) for ABTL0812 was established at 1300 mg tid. Most frequent hematological adverse events (AE) of the combination were neutropenia (52.9%), anemia (37.3%) and thrombocytopenia (19.6%). Nausea (66.7%), asthenia (66.7%), diarrhea (54.9%) and vomiting (54.9%) were the most frequent non-hematological adverse events (AEs). The combination of ABTL0812 plus CP showed an ORR of 65.8% (13.2% complete response and 52.6% partial response) with a median DOR of 7.4 months (95% CI: 6.3-10.8 months). Median PFS was 9.8 months (95% CI: 6.6-10.6) and median OS 23.6 months (95% CI 6.4-ND). Pharmacokinetic parameters were compatible with target engagement observed in preclinical studies, and blood pharmacodynamic biomarkers indicated sustained target regulation during, at least, 28 days after starting the treatment. CONCLUSIONS: This study suggests that the combination of ABTL0812 with CP is safe and feasible with an encouraging activity in patients with advanced/recurrent EC. Our data warrant further confirmation in prospective randomized trials. TRIAL REGISTRATION: EU Clinical Trial Register, EudraCT number 2016-001352-21 and National Clinical Trials Number, NCT03366480. Registration on 19 September 2016.

Occupational therapy in the management of haemophilia patients: A scoping review.

BACKGROUND: Haemophilia is a haematological disease, although most haemorrhages occur in the locomotor system. Patients are physically disabled from an early age and have a poorer perception of quality of life. In the day-to-day lives of patients and their families, psychosocial well-being, the disease's physical, personal, and social impact, as well as work-related problems are the most complicated aspects of the disease that need to be addressed. OBJECTIVE: To identify the role of occupational therapy in managing patients with haemophilia and to analyse the therapeutic potential of occupational therapy in treating these patients. METHODS: A scoping review was conducted to identify the role of occupational therapy in managing patients with haemophilia and to analyse the therapeutic potential of occupational therapy in treating these patients. The review was registered in the international registry PROSPERO (Id: CRD42022319637). The databases consulted were SCOPUS, PubMed, PsycINFO, Web of Science and Science Direct, including all studies published until 14 August 2023. RESULTS: No single study was found that specifically developed an occupational therapy intervention for patients with haemophilia. Measurement instruments have been identified, specific for patients with haemophilia and generic, that can be useful for the functional evaluation of these patients in the occupational therapy approach. Different studies showed the importance of multidisciplinary treatment, including occupational therapy. CONCLUSIONS: The use of occupational therapy could be effective in improving autonomy and quality of life in haemophilia patients. Therefore, it is of paramount importance to conduct research studies within the field of occupational therapy.

Clonal evolution mechanisms in NT5C2 mutant-relapsed acute lymphoblastic leukaemia.

Relapsed acute lymphoblastic leukaemia (ALL) is associated with resistance to chemotherapy and poor prognosis. Gain-of-function mutations in the 5'-nucleotidase, cytosolic II (NT5C2) gene induce resistance to 6-mercaptopurine and are selectively present in relapsed ALL. Yet, the mechanisms involved in NT5C2 mutation-driven clonal evolution during the initiation of leukaemia, disease progression and relapse remain unknown. Here we use a conditional-and-inducible leukaemia model to demonstrate that expression of NT5C2(R367Q), a highly prevalent relapsed-ALL NT5C2 mutation, induces resistance to chemotherapy with 6-mercaptopurine at the cost of impaired leukaemia cell growth and leukaemia-initiating cell activity. The loss-of-fitness phenotype of NT5C2+/R367Q mutant cells is associated with excess export of purines to the extracellular space and depletion of the intracellular purine-nucleotide pool. Consequently, blocking guanosine synthesis by inhibition of inosine-5'-monophosphate dehydrogenase (IMPDH) induced increased cytotoxicity against NT5C2-mutant leukaemia lymphoblasts. These results identify the fitness cost of NT5C2 mutation and resistance to chemotherapy as key evolutionary drivers that shape clonal evolution in relapsed ALL and support a role for IMPDH inhibition in the treatment of ALL.

Outcomes and factors associated with relapse of vaccine-induced liver injury after SARS CoV-2 immunization: A nationwide study.

INTRODUCTION AND OBJECTIVES: Different patterns of liver injury have been reported in association with the SARS-CoV-2 vaccines. The aim of this study was to describe a nationwide cohort of patients with SARS CoV-2 vaccine-induced liver injury, focusing on treatment and the evolution after further booster administration. PATIENTS AND METHODS: multicentre, retrospective-prospective study, including subjects who developed abnormal liver tests within 90 days after administration of SARS-CoV-2 vaccination. RESULTS: 47 cases were collected: 17 after prime dose and 30 after booster. Age was 57 years, 30 (63.8 %) were female, and 7 (14.9 %) had a history of prior autoimmune hepatitis (AIH). Most cases were non-severe, though 9 (19.1 %) developed acute liver injury or failure (ALF). Liver injury tended to be more severe in those presenting after a booster (p=0.084). Pattern of liver injury was hepatocellular (80.9 %), mixed (12.8 %) and 3 (6.4 %) cholestatic. Liver biopsy was performed on 33 patients; 29 showed findings of AIH. Forty-one (87.2 %) patients received immunosuppressants, mostly corticosteroids (35/41). One required liver transplantation and another died due to ALF. Immunosuppression was discontinued in 6/41 patients without later rebound. Twenty-five subjects received at least one booster and 7 (28.0 %) relapsed from the liver injury, but all were non-severe. Recurrence was less frequent among patients on immunosuppressants at booster administration (28.6 % vs. 88.9 %, p=0.007). CONCLUSIONS: SARS CoV-2 vaccine-induced liver injury is heterogeneous but mostly immune-mediated. Relapse of liver injury after re-exposure to vaccine is frequent (28.0 %) but mild. Immunosuppression at booster administration is associated with a lower risk of liver injury.

Hepatic focal lesions and constitutional syndrome, is it always cancer?

Hepatic focal lesions are a heterogeneous group of lesions that can be either benign or malignant in nature. They are typically diagnosed through ultrasound in all cases needing to rule out a metastatic nature. We present the case of a 51-year-old male from Morocco diagnosed with hepatic SOLs in the context of abdominal pain and constitutional syndrome.

Thrombocytopaenia and COVID-19 infection during pregnancy increases the risk of preeclampsia: a multicentre study.

RESEARCH QUESTION: Is a low platelet count related to an increased risk of severe disease in pregnant women with active severe acute respiratory syndrome coronavirus 2 infection? DESIGN: A cross-sectional multicentre study in pregnant women with COVID-19 confirmed by polymerase chain reaction, antigen test, antibody test, or all. RESULTS: A total of 153 pregnant women with COVID-19 were included in the study, of whom 12.4% had thrombocytopaenia. Pregnant women with thrombocytopaenia were on average 3.1 years older (95% CI 0.18 to 6.38) than women without thrombocytopaenia. Pregnant smokers had a higher risk of thrombocytopaenia than non-smokers (OR 6.55, CI 95% 1.29 to 33.13). B Rh negative (B Rh-) pregnant women had a much higher risk of thrombocytopaenia than pregnant women with other blood groups (OR 16.83, CI 95% 1.42 to 199.8). Pregnant women with thrombocytopaenia had a much higher risk of suffering from preeclampsia (OR 16.2, CI 95% 1.35 to 193.4). CONCLUSIONS: COVID-19 infection is not a risk factor for a low platelet count in pregnant women, although the risk is increased by smoking and in women with blood group B Rh-. In case of pregnancy with thrombocytopaenia, COVID-19 infection leads to an increased risk of preeclampsia.

A photobioreactor for production of algae biomass from gaseous emissions of an animal house.

Sustainable approaches to circular economy in animal agriculture are still poorly developed. Here, we report an approach to reduce gaseous emissions of CO2 and NH3 from animal housing while simultaneously using them to produce value-added biomass. To this end, a cone-shaped, helical photobioreactor was developed that can be integrated into animal housing by being freely suspended, thereby combining a small footprint with a physically robust design. The photobioreactor was coupled with the exhaust air of a chicken house to allow continuous cultivation of a mixed culture of Arthrospira spec. (Spirulina). Continuous quantification of CO2 and NH3 concentration showed that the coupled algae reactor effectively purifies the exhaust air from the chicken house while producing algal biomass. Typical production rates of greater than 0.3 g/l*day dry mass were obtained, and continuous operation was possible for several weeks. Morphological, biochemical, and genomic characterization of Spirulina cultures yielded insights into the dynamics and metabolic processes of the microbial community. We anticipate that further optimization of this approach will provide new opportunities for the generation of value-added products from gaseous CO2 and NH3 waste emissions, linking resource-efficient production of microalgae with simultaneous sequestration of animal emissions. KEY POINTS: • Coupling a bioreactor with exhaust gases of chicken coop for production of biomass. • Spirulina mixed culture removes CO2 and NH3 from chicken house emissions. • High growth rates and biodiversity adaptation for nitrogen metabolism. Towards a sustainable circular economy in livestock farming. The functional coupling of a helical tube photobioreactor with exhaust air from a chicken house enabled the efficient cultivation of Spirulina microalgae while simultaneously sequestering the animals' CO2 and NH3 emissions.

Organization of collagen fibers and tissue hardening: Markers of fibrotic scarring after spinal cord injury in mice revealed by multiphoton-atomic force microscopy imaging.

Spinal cord injury is a dramatic disease leading to severe motor, sensitive and autonomic impairments. After injury the axonal regeneration is partly inhibited by the glial scar, acting as a physical and chemical barrier. The scarring process involves microglia, astrocytes and extracellular matrix components, such as collagen, constructing the fibrotic component of the scar. To investigate the role of collagen, we used a multimodal label-free imaging approach combining multiphoton and atomic force microscopy. The second harmonic generation signal exhibited by fibrillar collagen enabled to specifically monitor it as a biomarker of the lesion. An increase in collagen density and the formation of more tortuous fibers over time after injury are observed. Nano-mechanical investigations revealed a noticeable hardening of the injured area, correlated with collagen fibers' formation. These observations indicate the concomitance of important structural and mechanical modifications during the fibrotic scar evolution.

Dosage of Physical Activity to Avoid Impairment of Activities Due to Pain: Analysis of Population-based Conditional Processes.

BACKGROUND: Physical activity's established health benefits include pain control, yet there is no consensus on the required dosage according to the literature. AIM: To test the influence of exercise on perceived health in patients whose daily activities are limited due to pain. Besides, analyze the possible moderating effect of age and find a formula for exercise dosage based on the perceived level of health. METHODS: Cross-sectional study based on the 2017 Spanish National Health Survey with 4,123 participants reporting activity limitations in their daily activities due to pain. The International Physical Activity Questionnaire (short version) was used to calculate energy expenditure. Data included age, sex, leisure-time physical activity, sitting time, pain-related impairments, pain medication, and perceived health. Mediation regression analysis was conducted using the SPSS PROCESS 4.0 macro. RESULTS: Results indicate a decline in perceived health with age. The relationship between exercise (energy expenditure) and perceived health was highly significant (d=-0.224, p<0.001). Age moderated the association between pain and energy expenditure up to 75.61 years (0.1568, p=0.05) and between energy expenditure and perceived health up to 75.74 years (-0.289, p=0.05), but this effect diminished afterwards. A formula was developed to estimate energy expenditure based on the desired level of health. CONCLUSIONS: The perception of health in people who are limited in their daily activities due to pain (moderate to very much) is mediated by the amount of physical activity they perform. Besides, this perception is moderated by age, up to 76 years.

Heterogenous Differences in Cellular Senescent Phenotypes in Pre-Eclampsia and IUGR following Quantitative Assessment of Multiple Biomarkers of Senescence.

Premature ageing of the placenta in pregnancy outcomes is associated with the persistent presence of oxidative stress and placental insufficiency reducing its functional capacity. In this study, we investigated cellular senescence phenotypes of pre-eclampsia and IUGR pregnancies by simultaneously measuring several biomarkers of senescence. Maternal plasma and placental samples were collected at term gestation from nulliparous women undergoing pre-labour elective caesarean section with pre-eclampsia without intrauterine growth restriction (PE; n = 5), pre-eclampsia associated with intrauterine growth restriction (n = 8), intrauterine growth restriction (IUGR < 10th centile; n = 6), and age-matched controls (n = 20). Placental absolute telomere length and senescence gene analysis was performed by RTqPCR. The expression of cyclin-dependent kinase inhibitors (p21 and p16) was determined by Western blot. Senescence-associated secretory phenotypes (SASPs) were evaluated in maternal plasma by multiplex ELISA assay. Placental expression of senescence-associated genes showed significant increases in CHEK1, PCNA, PTEN, CDKN2A, and CCNB-1 (p < 0.05) in pre-eclampsia, while TBX-2, PCNA, ATM, and CCNB-1 expression were evident (p < 0.05) and were significantly decreased in IUGR compared with controls. Placental p16 protein expression was significantly decreased in pre-eclampsia only compared with controls (p = 0.028). IL-6 was significantly increased in pre-eclampsia (0.54 pg/mL ± 0.271 vs. 0.3 pg/mL ± 0.102; p = 0.017) while IFN-γ was significantly increased in IUGR (4.6 pg/mL ± 2.2 vs. 2.17 pg/mL ± 0.8; p = 0.002) compared with controls. These results provide evidence of premature senescence in IUGR pregnancies, and while cell cycle checkpoint regulators are activated in pre-eclampsia, the cellular phenotype is one of cell repair and subsequent proliferation rather than progression to senescence. The heterogeneity of these cellular phenotypes highlights the complexity of characterising cellular senescence and may equally be indicative of the differing pathophysiological insults unique to each obstetric complication.

Derivation of Limbal Stem Cells from Human Adult Mesenchymal Stem Cells for the Treatment of Limbal Stem Cell Deficiency.

Approximately 10 million individuals have blindness due to limbal stem cell (LSCs) deficiency, one of the most challenging problems in ophthalmology. To replenish the LSC pool, an autologous extraocular cell source is appropriate, thereby avoiding the risk of immune rejection, the need for immunosuppression and the risk of damaging the contralateral eye. In recent years, adipose-derived mesenchymal stem cells (ADSCs) have been a key element in ocular regenerative medicine. In this study, we developed a protocol for deriving human LSCs from ADSCs compatible with the standard carrier human amniotic membrane, helping provide a stem cell pool capable of maintaining proper corneal epithelial homeostasis. The best protocol included an ectodermal induction step by culturing ADSCs with media containing fetal bovine serum, transforming growth factor-ß inhibitor SB-505124, Wnt inhibitor IWP-2 and FGF2 for 7 days, followed by an LSC induction step of culture in modified supplemental hormonal epithelial medium supplemented with pigment epithelium-derived factor and keratinocyte growth factor for 10 additional days. The optimal differentiation efficiency was achieved when cells were cultured in this manner over vitronectin coating, resulting in up to 50% double-positive αp63/BMI-1 cells. The results of this project will benefit patients with LSC deficiency, aiding the restoration of vision.

Prognostic Role of Neutrophil, Monocyte and Platelet to Lymphocyte Ratios in Advanced Ovarian Cancer According to the Time of Debulking Surgery.

Despite a multimodal radical treatment, mortality of advanced epithelial ovarian cancer (AEOC) remains high. Host-related factors, such as systemic inflammatory response and its interplay with the immune system, remain underexplored. We hypothesized that the prognostic impact of this response could vary between patients undergoing primary debulking surgery (PDS) and those undergoing interval debulking surgery (IDS). Therefore, we evaluated the outcomes of two surgical groups of newly diagnosed AEOC patients according to the neutrophil, monocyte and platelet to lymphocyte ratios (NLR, MLR, PLR), taking median ratio values as cutoffs. In the PDS group (n = 61), low NLR and PLR subgroups showed significantly better overall survival (not reached (NR) vs. 72.7 months, 95% confidence interval [CI]: 40.9-95.2, p = 0.019; and NR vs. 56.1 months, 95% CI: 40.9-95.2, p = 0.004, respectively) than those with high values. Similar results were observed in progression free survival. NLR and PLR-high values resulted in negative prognostic factors, adjusting for residual disease, BRCA1/2 status and stage (HR 2.48, 95% CI: 1.03-5.99, p = 0.043, and HR 2.91, 95% CI: 1.11-7.64, p = 0.03, respectively). In the IDS group (n = 85), ratios were not significant prognostic factors. We conclude that NLR and PLR may have prognostic value in the PDS setting, but none in IDS, suggesting that time of surgery can modulate the prognostic impact of baseline complete blood count (CBC).

Emotional empowerment through information research and communication to reduce fear of COVID-19 among nursing students: a randomised controlled trial.

BACKGROUND: Despite an existing body of literature on anxiety reduction using multi-component methods, little is known about the effect of active student participation in research and communication of scientific information on anxiety and fear reduction. The aim of this study is to evaluate the impact of quality scientific information research and the production of informative videos on the preventive aspects of COVID-19 on fear and anxiety reduction. METHODS: A randomised controlled trial was conducted with 220 undergraduate nursing students in the first year of the nursing degree. The participating students were randomised into two groups. The experimental group carried out an intervention based on a database search for information on preventing COVID-19 and production of a video giving scientific reasons why prevention measures should be followed. In the control group, students created posters and videos about theoretical aspects of one module of the nursing degree. Both groups were surveyed before and after the intervention, measuring their state of resilience, preventive behaviours, level of anxiety, and fear of COVID-19. RESULTS: The intervention group showed a greater decrease in fear levels after the intervention than those in the control group. There were no differences between the groups in terms of resilience, preventive behaviours, or anxiety. In the experimental group, there was a significant decrease in anxiety levels and fear levels after the intervention compared to the baseline levels. CONCLUSIONS: An intervention based on active participation in searches for high-quality scientific information and production of information videos on COVID-19 prevention reduced fear and anxiety caused by COVID-19 among nursing students. TRIAL REGISTRATION: We have retrospectively registered the trial in Open Science Framework and the identification number is https://doi.org/10.17605/OSF.IO/6QU5S .

Training and competence in Digestive Endoscopy: Statement Position Paper from the Spanish Society of Digestive Diseases.

Gastrointestinal (GI) Endoscopy is a basic competence for the management of gastrointestinal diseases. However, it should not be regarded as an independent training technique. Rather it is a part of a continuous and accredited process that requires clinical knowledge from the gastroenterologist to keep skills up-to-date in a constantly evolving medical subspecialty. Thus, the only official accredited way for training in GI endoscopy is through the Specialized Health Training program in the Management of the Digestive Diseases administered by the Spanish Ministry of Health.

Oportunistic diagnosis based on age and hepatitis C virus clearance: an essential step to improve the overall health of the liver.

Back in January 2022, an EASL-Lancet Commission on the impact of liver disorders in the European region commissioned by the WHO demonstrated that this condition is, actually, the second leading cause of loss of labor years in Europe after ischemic heart disease (1). This is a very relevant piece of information since this is something that is going to impact the new generations of Europeans unless a significant change is made in public health policies. Despite the advances made over the last few years in hepatitis C virus clearance-understood as a significant reduction of morbidity and mortality associated with Hepatitis B and C viruses-there are still challenges ahead to improve liver health due to the high use of alcohol, and the inseparable triad obesity / diabetes mellitus / metabolic associated fatty liver disease. Also, access to healthcare for several population groups at risk of presenting higher rates of liver disease has become a problem.

Emergency Management of Electrical Storm: A Practical Overview.

Electrical storm is a medical emergency characterized by ventricular arrythmia recurrence that can lead to hemodynamic instability. The incidence of this clinical condition is rising, mainly in implantable cardioverter defibrillator patients, and its prognosis is often poor. Early acknowledgment, management and treatment have a key role in reducing mortality in the acute phase and improving the quality of life of these patients. In an emergency setting, several measures can be employed. Anti-arrhythmic drugs, based on the underlying disease, are often the first step to control the arrhythmic burden; besides that, new therapeutic strategies have been developed with high efficacy, such as deep sedation, early catheter ablation, neuraxial modulation and mechanical hemodynamic support. The aim of this review is to provide practical indications for the management of electrical storm in acute settings.

Left Atrial Appendage Closure: A Current Overview Focused on Technical Aspects and Different Approaches.

Several studies in literature have shown that 90% of emboli related to non-valvular atrial fibrillation originate from left atrial appendage. Percutaneous closure or surgical exclusion of left atrial appendage in patients with high bleeding and high cardioembolic risk is currently a well established procedure in literature, clinical practice and guidelines. Knowledge of different techniques of left atrial appendage closure is necessary to individualize the procedure according to the patient anatomy and pre-procedural imaging evaluations. In this review the authors will evaluate different left atrial appendage closure systems and the different pre and intra procedural imaging methods.

Role of H4K16 acetylation in 53BP1 recruitment to double-strand break sites in in vitro aged cells.

Increased frequency of DNA double strand breaks (DSBs) with aging suggests an age-associated decline in DSB repair efficiency, which is also influenced by the epigenetic landscape. H4 acetylation at lysine 16 (H4K16Ac) has been related to DSB repair since deacetylation of this mark is required for efficient 53BP1 recruitment to DSBs. Although age-associated changes in H4K16Ac levels have been studied, their contribution to age-related DSB accumulation remains unknown. In vitro aged Human Dermal Fibroblasts (HDFs) display lower levels of H4K16A that correlate with reduced recruitment of 53BP1 to basal DSBs. Following DNA damage induction, early passage (EP) cells suffered from a transient H4K16 deacetylation that allowed proper 53BP1 recruitment to DSBs. In contrast, to reach this specific and optimum level, aged cells responded by increasing their overall lower H4K16Ac levels. Induced hyperacetylation of late passage (LP) cells using trichostatin A increased H4K16Ac levels but did not ameliorate 53BP1 recruitment. Instead, deacetylation induced by MOF silencing reduced H4K16Ac levels and compromised 53BP1 recruitment in both EP and LP cells. Age-associated decrease of H4K16Ac levels contributes to the repair defect displayed by in vitro aged cells. H4K16Ac responds to DNA damage in order to reach a specific, optimum level that allows proper 53BP1 recruitment. This response may be compromised with age, as LP cells depart from lower H4K16Ac levels. Variations in H4K16Ac following the activation of the DNA damage response and aging point at this histone mark as a key mediator between DNA repair and age-associated chromatin alterations.