Oncogenic Role of Fusion-circRNAs Derived from Cancer-Associated Chromosomal Translocations.

Chromosomal translocations encode oncogenic fusion proteins that have been proven to be causally involved in tumorigenesis. Our understanding of whether such genomic alterations also affect non-coding RNAs is limited, and their impact on circular RNAs (circRNAs) has not been explored. Here, we show that well-established cancer-associated chromosomal translocations give rise to fusion circRNAs (f-circRNA) that are produced from transcribed exons of distinct genes affected by the translocations. F-circRNAs contribute to cellular transformation, promote cell viability and resistance upon therapy, and have tumor-promoting properties in in vivo models. Our work expands the current knowledge regarding molecular mechanisms involved in cancer onset and progression, with potential diagnostic and therapeutic implications.

MYC regulates the core pre-mRNA splicing machinery as an essential step in lymphomagenesis.

Deregulated expression of the MYC transcription factor occurs in most human cancers and correlates with high proliferation, reprogrammed cellular metabolism and poor prognosis. Overexpressed MYC binds to virtually all active promoters within a cell, although with different binding affinities, and modulates the expression of distinct subsets of genes. However, the critical effectors of MYC in tumorigenesis remain largely unknown. Here we show that during lymphomagenesis in Eµ-myc transgenic mice, MYC directly upregulates the transcription of the core small nuclear ribonucleoprotein particle assembly genes, including Prmt5, an arginine methyltransferase that methylates Sm proteins. This coordinated regulatory effect is critical for the core biogenesis of small nuclear ribonucleoprotein particles, effective pre-messenger-RNA splicing, cell survival and proliferation. Our results demonstrate that MYC maintains the splicing fidelity of exons with a weak 5' donor site. Additionally, we identify pre-messenger-RNAs that are particularly sensitive to the perturbation of the MYC-PRMT5 axis, resulting in either intron retention (for example, Dvl1) or exon skipping (for example, Atr, Ep400). Using antisense oligonucleotides, we demonstrate the contribution of these splicing defects to the anti-proliferative/apoptotic phenotype observed in PRMT5-depleted Eµ-myc B cells. We conclude that, in addition to its well-documented oncogenic functions in transcription and translation, MYC also safeguards proper pre-messenger-RNA splicing as an essential step in lymphomagenesis.

Regulation of constitutive and alternative splicing by PRMT5 reveals a role for Mdm4 pre-mRNA in sensing defects in the spliceosomal machinery.

The tight control of gene expression at the level of both transcription and post-transcriptional RNA processing is essential for mammalian development. We here investigate the role of protein arginine methyltransferase 5 (PRMT5), a putative splicing regulator and transcriptional cofactor, in mammalian development. We demonstrate that selective deletion of PRMT5 in neural stem/progenitor cells (NPCs) leads to postnatal death in mice. At the molecular level, the absence of PRMT5 results in reduced methylation of Sm proteins, aberrant constitutive splicing, and the alternative splicing of specific mRNAs with weak 5' donor sites. Intriguingly, the products of these mRNAs are, among others, several proteins regulating cell cycle progression. We identify Mdm4 as one of these key mRNAs that senses the defects in the spliceosomal machinery and transduces the signal to activate the p53 response, providing a mechanistic explanation of the phenotype observed in vivo. Our data demonstrate that PRMT5 is a master regulator of splicing in mammals and uncover a new role for the Mdm4 pre-mRNA, which could be exploited for anti-cancer therapy.

The municipal solid waste management of La Paz (Bolivia): Challenges and opportunities for a sustainable development.

Municipal solid waste management (MSWM) is considered an important public health, economic and environmental concern, especially in developing countries. This paper introduces the situation of MSWM in La Paz (Bolivia) in 2016, and is based on the Wasteaware indicators and waste flow analysis, useful tools for classifying and comparing waste treatment and management plans among other countries. Taking into account the lack of technology in waste treatment and the presence of a developed informal sector, the paper analyses the main strengths and weak points for implementing a sustainable MSWM. The research conducted revealed that the MSWM of La Paz is not efficient with regard to collection, recycling (8%), financial sustainability, and equity of the service. At the same time, local Government and stakeholders are interested in implementing new MSWM methods for improving the current sanitary state of the city and many efforts were made over the last ten years. In general terms, La Paz could be considered as a good study area for developing plans for waste valorization, becoming an example for a low-middle income developing big city of Latin America. The study provided a few considerations about the affordability of the methodology applied and critically analyzed the case study proposed.

Hairless promotes PPARγ expression and is required for white adipogenesis.

Adipose tissue is the largest compartment in the mammalian body for storing energy as fat, providing an important reservoir of fuel for maintaining whole body energy homeostasis. Herein, we identify the transcriptional cofactor hairless (HR) to be required for white adipogenesis. Moreover, forced expression of HR in non-adipogenic precursor cells induces adipogenic gene expression and enhances adipocyte formation under permissive conditions. HR exerts its proadipogenic effects by regulating the expression of PPARγ, one of the central adipogenic transcription factors. In conclusion, our data provide a new mechanism required for white adipogenesis.

p53-Independent regulation of p21Waf1/Cip1 expression and senescence by PRMT6.

p21 is a potent cyclin-dependent kinase inhibitor that plays a role in promoting G1 cell cycle arrest and cellular senescence. Consistent with this role, p21 is a downstream target of several tumour suppressors and oncogenes, and it is downregulated in the majority of tumours, including breast cancer. Here, we report that protein arginine methyltransferase 6 (PRMT6), a type I PRMT known to act as a transcriptional cofactor, directly represses the p21 promoter. PRMT6 knock-down (KD) results in a p21 derepression in breast cancer cells, which is p53-independent, and leads to cell cycle arrest, cellular senescence and reduced growth in soft agar assays and in severe combined immunodeficiency (SCID) mice for all the cancer lines examined. We finally show that bypassing the p21-mediated arrest rescues PRMT6 KD cells from senescence, and it restores their ability to grow on soft agar. We conclude that PRMT6 acts as an oncogene in breast cancer cells, promoting growth and preventing senescence, making it an attractive target for cancer therapy.

Comparison of Two Extubation Techniques in Critically Ill Adult Subjects: The ExtubAR Randomized Clinical Trial.

BACKGROUND: Two orotracheal extubation techniques are described in the literature: the traditional technique and the positive-pressure technique. Although prior studies reported better clinical outcomes with the positive-pressure extubation technique, its superiority has not been extensively studied yet. This study was to determine whether the positive-pressure orotracheal extubation technique, compared with the traditional orotracheal extubation technique, reduces the incidence of major postextubation complications (up to 60 min) in critically ill adult subjects. METHODS: This was a multi-center randomized clinical trial. Subjects age > 18 y, requiring invasive mechanical ventilation through an endotracheal tube, who met the orotracheal extubation criteria were included and randomized to traditional extubation group (removing the endotracheal tube by applying continuous endotracheal suctioning during the entire procedure) or positive-pressure group (application of pressure support mode at 15/10 cm H2O during cuff deflation and extubation). The primary measure was postextubation major complications, defined as the clinical evidence of at least one of the following: desaturation, upper-airway obstruction, or vomiting. RESULTS: A total of 725 subjects was randomly assigned to the traditional extubation group (n = 358) and positive-pressure group (n = 367). Seventeen subjects were eliminated and not included in the per-protocol analysis. Of 708 subjects, 185 (26.1%) developed at least one major complication. The incidence was 27.8% (96/345) in the traditional group compared with 24.5% (89/363) in the positive-pressure group. No statistically significant differences were observed between the 2 groups (absolute risk 3% [95 CI -3 to 10]; relative risk, 0.88 [95 CI 0.69-1.13], P = .32). CONCLUSIONS: Despite the trend toward the positive-pressure group, no statistically significant differences were observed. Our findings agree with the literature in that positive-pressure extubation is a safe procedure; therefore, both techniques may be used during extubation in critically ill adult patients.

[Structural capacity, technological human resources and mechanical ventilation requirements in 58 intensive care units in Argentina during the SARS-CoV-2 pandemic. A SATICOVID-19 Study]. / Capacidad estructural, recursos humanos tecnológicos y requerimientos de ventilación mecánica en 58 unidades de cuidados intensivos en Argentina durante la pandemia por SARS-CoV-2. Estudio SATICOVID-19.

During the SARS-CoV-2 pandemic, there was a marked requirement for critical care beds, supplies and trained professionals to assist patients with severe respiratory failure. The Argentine Society of Intensive Care (SATI) designed a study to characterize these aspects in intensive care units (ICUs). Multicenter, prospective cohort study; the participating ICUs completed a form at the end of the study (31/10/2020) on hospital characteristics, number of beds in pre- and intra-pandemic critical areas, incorporation of professionals, technological resources, and workload. Fifty-eight ICUs participated; 28(48%) were located in Buenos Aires Province, 22(38%) in Buenos Aires Autonomous City and 10 (17%) in other provinces; 31 (53%) of UCIs belonged to the public sector; 23 (47%) to the private-social security. In 35/58 (60%) of the hospitals critical care beds increased from 902 to 1575 (75%), 37% in ICU and 63% mainly in Coronary Care Unit and Emergency-shock room. In 41/55 (75%) UCIs, staff were incorporated: 27(49%) physicians (70% intensivists), 36 (65%) nurses, 28 (51%) respiratory therapists, 20(36%) cleaning staff, and 1(2%) others. A 96% of the ICUS reported having sufficient ventilators and 95% enough supplies and PPE. Of all patients on invasive mechanical ventilation, 55% [43-64] had COVID-19. Oxygen therapy was required as noninvasive support in 14% [8-24] of COVID-19 admissions. There was a significant expansion of critical operational areas, secondary to the increase in beds, staff, and adequate availability of ventilators and essential supplies. The burden of critical illness from COVID-19 was intense, with more than half of patients on mechanical ventilation.

Durante la pandemia por SARS-CoV-2 hubo un marcado requerimiento de camas de cuidados críticos, insumos y profesionales entrenados para asistir a pacientes con insuficiencia respiratoria grave. La Sociedad Argentina de Terapia Intensiva (SATI) diseñó un estudio para caracterizar estos aspectos en las Unidades de Cuidados Intensivos (UCIs). Estudio multicéntrico, de cohorte prospectiva; las UCIs participantes completaron un formulario al final del estudio (31/10/2020) sobre características hospitalarias, número de camas de áreas críticas pre- e intra-pandemia, incorporación de profesionales, insumos y recursos tecnológicos, y carga de trabajo. Participaron 58 UCIs; 28(48%) de Provincia de Buenos Aires, 22(38%) de Ciudad Autónoma de Buenos Aires, 10(17%) de otras; 31(53%) UCIs pertenecían al sector público; 23(47%) al privado-seguridad social. En 35/58(60%) hospitales las camas de cuidados críticos aumentaron de 902 a 1575(75%); 37% en UCI y 63% principalmente en Unidad Coronaria y Emergencias-shock room. En 41/55(75%) UCIs se incorporó personal: 27(49%) médicos/as (70% intensivistas), 36(65%) enfermeros/as, 28(51%) kinesiólogos/as, 20(36%) personal de limpieza, y 1(2%) otros/as; 96% de las UCIS reportaron disponer de respiradores suficientes, y 95%, insumos y EPP suficientes. De todos los pacientes en ventilación mecánica invasiva, 55% [43-64] presentaron COVID-19. Se requirió oxigenoterapia como soporte no invasivo en 14% [8-24] de los ingresos por COVID-19. Se registró una importante expansión de las áreas críticas operativas, secundariamente al aumento de camas, personal, y adecuada disponibilidad de respiradores e insumos esenciales. La carga de la enfermedad crítica por COVID-19 fue intensa, constituyendo más de la mitad de los pacientes en ventilación mecánica.

Clinical characteristics, respiratory management, and determinants of oxygenation in COVID-19 ARDS: A prospective cohort study.

PURPOSE: To identify determinants of oxygenation over time in patients with COVID-19 acute respiratory distress syndrome (ARDS); and to analyze their characteristics according to Berlin definition categories. MATERIALS AND METHODS: Prospective cohort study including consecutive mechanically ventilated patients admitted between 3/20/2020-10/31/2020 with ARDS. Epidemiological and clinical data on admission; outcomes; ventilation, respiratory mechanics and oxygenation variables were registered on days 1, 3 and 7 for the entire population and for ARDS categories. RESULTS: 1525 patients aged 61 ± 13, 69% male, met ARDS criteria; most frequent comorbidities were obesity, hypertension, diabetes and respiratory disease. On admission, 331(21%), 849(56%) and 345(23%) patients had mild, moderate and severe ARDS; all received lung-protective ventilation (mean tidal volumes between 6.3 and 6.7 mL/kg PBW) and intermediate PEEP levels (10-11 cmH2O). PaO2/FiO2, plateau pressure, static compliance, driving pressure, ventilation ratio, pH and D-dimer >2 mg/L remained significantly different among the ARDS categories over time. In-hospital mortality was, respectively, 55%, 58% and 70% (p < 0.000). Independent predictors of changes of PaO2/FiO2 over time were BMI; preexistent respiratory disease; D-dimer >2 mg/L; day 1-PEEP, and day 1-ventilatory ratio. CONCLUSION: Hypoxemia in patients with COVID-19-related ARDS is associated with comorbidities, deadspace and activated coagulation markers, and disease severity-reflected by the PEEP level required.

Clinical characteristics and outcomes of invasively ventilated patients with COVID-19 in Argentina (SATICOVID): a prospective, multicentre cohort study.

BACKGROUND: Although COVID-19 has greatly affected many low-income and middle-income countries, detailed information about patients admitted to the intensive care unit (ICU) is still scarce. Our aim was to examine ventilation characteristics and outcomes in invasively ventilated patients with COVID-19 in Argentina, an upper middle-income country. METHODS: In this prospective, multicentre cohort study (SATICOVID), we enrolled patients aged 18 years or older with RT-PCR-confirmed COVID-19 who were on invasive mechanical ventilation and admitted to one of 63 ICUs in Argentina. Patient demographics and clinical, laboratory, and general management variables were collected on day 1 (ICU admission); physiological respiratory and ventilation variables were collected on days 1, 3, and 7. The primary outcome was all-cause in-hospital mortality. All patients were followed until death in hospital or hospital discharge, whichever occurred first. Secondary outcomes were ICU mortality, identification of independent predictors of mortality, duration of invasive mechanical ventilation, and patterns of change in physiological respiratory and mechanical ventilation variables. The study is registered with ClinicalTrials.gov, NCT04611269, and is complete. FINDINGS: Between March 20, 2020, and Oct 31, 2020, we enrolled 1909 invasively ventilated patients with COVID-19, with a median age of 62 years [IQR 52-70]. 1294 (67·8%) were men, hypertension and obesity were the main comorbidities, and 939 (49·2%) patients required vasopressors. Lung-protective ventilation was widely used and median duration of ventilation was 13 days (IQR 7-22). Median tidal volume was 6·1 mL/kg predicted bodyweight (IQR 6·0-7·0) on day 1, and the value increased significantly up to day 7; positive end-expiratory pressure was 10 cm H2O (8-12) on day 1, with a slight but significant decrease to day 7. Ratio of partial pressure of arterial oxygen (PaO2) to fractional inspired oxygen (FiO2) was 160 (IQR 111-218), respiratory system compliance 36 mL/cm H2O (29-44), driving pressure 12 cm H2O (10-14), and FiO2 0·60 (0·45-0·80) on day 1. Acute respiratory distress syndrome developed in 1672 (87·6%) of patients; 1176 (61·6%) received prone positioning. In-hospital mortality was 57·7% (1101/1909 patients) and ICU mortality was 57·0% (1088/1909 patients); 462 (43·8%) patients died of refractory hypoxaemia, frequently overlapping with septic shock (n=174). Cox regression identified age (hazard ratio 1·02 [95% CI 1·01-1·03]), Charlson score (1·16 [1·11-1·23]), endotracheal intubation outside of the ICU (ie, before ICU admission; 1·37 [1·10-1·71]), vasopressor use on day 1 (1·29 [1·07-1·55]), D-dimer concentration (1·02 [1·01-1·03]), PaO2/FiO2 on day 1 (0·998 [0·997-0·999]), arterial pH on day 1 (1·01 [1·00-1·01]), driving pressure on day 1 (1·05 [1·03-1·08]), acute kidney injury (1·66 [1·36-2·03]), and month of admission (1·10 [1·03-1·18]) as independent predictors of mortality. INTERPRETATION: In patients with COVID-19 who required invasive mechanical ventilation, lung-protective ventilation was widely used but mortality was high. Predictors of mortality in our study broadly agreed with those identified in studies of invasively ventilated patients in high-income countries. The sustained burden of COVID-19 on scarce health-care personnel might have contributed to high mortality over the course of our study in Argentina. These data might help to identify points for improvement in the management of patients in middle-income countries and elsewhere. FUNDING: None. TRANSLATION: For the Spanish translation of the Summary see Supplementary Materials section.

Incidence of immediate postextubation complications in critically Ill adult patients.

BACKGROUND: Postextubation complication rates vary among studies. It is necessary to standardize a method to identify postextubation complications and determine their potential association with extubation failure and reintubation in critically ill adult patients. OBJECTIVES: To describe immediate (up to 60 min) endotracheal postextubation complications in critically ill adult patients and determine whether these complications are associated with extubation failure. METHODS: Secondary analysis of a Randomized Clinical Trial that included 240 critically ill adult patients, who were eligible for extubation. Overall complications include at least one major complication (upper airway obstruction, desaturation, vomiting, post-obstructive pulmonary edema) and/or minor complications (bronchospasm, severe cough, hypertension, tachycardia, tachypnea, poor respiratory mechanics). RESULTS: Incidence of overall, major and minor complications was 71.2%, 30.9% and 62.7%, respectively. Forty (16.9%) patients failed extubation, and thirty (12.7%) were reintubated. Of 168 patients who developed a postextubation complication, 137 (81.5%) were successfully extubated. Only major complications were significantly associated with reintubation after extubation failure (p<0.001). CONCLUSION: We have observed high incidence rates of overall, major and minor complications. The development of major complications was statistically significantly associated with extubation failure and reintubation. It is still unknown whether the identification and treatment of immediate postextubation complications have positive effects on patients' clinical course or whether the complications are a mere effect of the extubation procedure.

Impact of implementing a protocol of respiratory care measures and optimization of mechanical ventilation in potential lung donors. / Impacto de la implementación de medidas de cuidados respiratorios y optimización de la ventilación mecánica en potenciales donantes de pulmón.

OBJECTIVE: To describe the results from the implementation of a respiratory care and mechanical ventilation protocol on potential lung donors who met the conditions for procurement. The secondary objective is to compare the results with historical data. METHODS: This was a retrospective, observational study. It included potential donors suitable for procurement of organs who had brain death and were hospitalized in critical care units of the Autonomous City of Buenos Aires from April 2017 to March 2018. Main variables: number of potential lung donors that reached the objective of procurement, rate of lungs procured, and rate of implanted lungs. Values of p < 0.05 were considered significant. RESULTS: Thirty potential lung donors were included, and 23 (88.5%; 95%CI 69.8 - 97.6) met the oxygenation objective. Twenty potential lung donors donated organs, of whom eight donated lungs, with which four double lung transplants and eight single lung transplants were performed. Seven of 12 lungs were procured and implanted in the preprotocol period, while all 12 were under the protocol (p = 0.38). The implantation rate was 58.3% (7/12) in the historical control period and 100% (12/12) (p = 0.04) in the study period.

OBJETIVO: Describir los resultados de la implementación de un protocolo de cuidados respiratorios y de ventilación mecánica en el potencial donante de pulmón, que cumplen las condiciones para ser procurados. El objetivo secundario es comparar los resultados con datos históricos. MÉTODOS: Estudio retrospectivo y observacional. Incluye potenciales donantes aptos para procuración de órganos con muerte encefálica internados en las áreas críticas de la Ciudad Autónoma de Buenos Aires, desde abril de 2017 hasta marzo de 2018. Variables principales: número de potencial donante de pulmón que alcanzan el objetivo de procuración, tasa de pulmones procurados y tasa de pulmones implantados. Se consideraron valores significativos p < 0,05. RESULTADOS: Se incluyeron 30 potenciales donantes de pulmón, 23 (88.5%; IC95% 69,8 - 97,6) cumplieron el objetivo de oxigenación. Veinte potenciales donantes de pulmón donaron órganos y de ellos, ocho donaron pulmones, con los cuales se realizaron 4 trasplantes bipulmonares y 8 unipulmonares. Los pulmones procurados e implantados en el periodo pre-protocolo fueron 7, mientras que durante el protocolo fueron 12 (valor p = 0,38). La tasa de implantación fue 58,3% (7/12) en el control histórico y 100% (12/12) (valor p = 0,04) en el periodo de estudio. CONCLUSIÓN: El protocolo permitió alcanzar el objetivo de oxigenación en la mayoría de los potenciales donantes de pulmón y una mejoría estadísticamente significativa en la tasa de implantación.

Survey on the extubation procedure in intensive care units in Buenos Aires, Argentina. / Encuesta sobre el procedimiento de extubación en las unidades de cuidados intensivos de Buenos Aires, Argentina.

OBJECTIVE: To examine the usual practice of airway management during the extubation procedure through an online survey to professionals working in intensive care units in the Autonomous City of Buenos Aires and in the Province of Buenos Aires, Argentina. METHODS: A cross-sectional descriptive study online survey was conducted from February 11 to March 11, 2013. A database was generated, and a voluntary and anonymous invitation to access the survey was sent by email to 500 participants. RESULTS: Out of a total of 500 participants, 217 (44%) responded to the survey, of whom 59.4% were physical therapists. One hundred ninety-five (89.9%) professionals were working in adult care. Regarding the cuff deflation procedure and extubation, 203 (93.5%) performe endotracheal suctioning, and 27 (12.5%) use positive pressure. Approximately 53.5% of participants reported having experienced immediate complications with this procedure in the last three months. In all, 163 complications were reported, and stridor was the most prevalent (52.7%). CONCLUSION: Most professionals working in intensive care units in the Autonomous City of Buenos Aires and in the Province of Buenos Aires, Argentina, use endotracheal suctioning without applying positive pressure during extubation.

OBJETIVO: Conocer la práctica habitual del manejo de la vía aérea durante el procedimiento de extubación mediante una encuesta online a profesionales de las unidades de cuidados intensivos de la Ciudad Autónoma de Buenos Aires y Provincia de Buenos, Argentina. MÉTODOS: Estudio descriptivo transversal de tipo encuesta online del 11 de febrero al 11 de marzo de 2013. Se envió por correo electrónico una invitación voluntaria y anónima para acceder a la encuesta a 500 participantes a partir de una base de datos confeccionada por los investigadores de este estudio. RESULTADOS: De un total de 500 participantes, 217 (44%) respondieron la encuesta. El 59,4% son kinesiólogos. Ciento noventa y cinco (89,9%) profesionales se desempeñan en atención de adultos. Con respecto al procedimiento de desinflado del balón y extubación, 203 (93,5%) realizan aspiración endotraqueal y 27 (12,5%) emplean presión positiva. El 53,5% de los participantes informó haber tenido en los últimos 3 meses complicaciones inmediatas a este procedimiento. Se informaron un total de 163 complicaciones, siendo el estridor el más prevalente (52,7%). CONCLUSIÓN: La mayoría de los profesionales de unidades de cuidados intensivos de la Ciudad Autónoma de Buenos Aires y Provincia de Buenos Aires, Argentina, emplea aspiración endotraqueal sin aplicar presión positiva durante el procedimiento de extubación.

Safety of Positive Pressure Extubation Technique.

BACKGROUND: Laboratory studies suggest applying positive pressure without endotracheal suction during cuff deflation and extubation. Although some studies reported better physiological outcomes (e.g. arterial blood gases) with this technique, the safety of positive pressure extubation technique has not been well studied. The aim of this study was to determine the safety of the positive-pressure extubation technique compared with the traditional extubation technique in terms of incidence of complications. METHODS: Adult subjects who were critically ill and on invasive mechanical ventilation who met extubation criteria were included. The subjects were randomly assigned to positive-pressure extubation (n = 120) or to traditional extubation (n = 120). Sequential tests for noninferiority and, when appropriate, for superiority were performed. Positive pressure was considered noninferior if the upper limit of the CI for the absolute risk difference did not exceed a threshold of 15% in favor of the traditional group, both in per protocol and intention-to-treat analyses. A P value of <.05 was considered significant. RESULTS: A total of 236 subjects were included in the primary analysis (per protocol) (119 in the positive-pressure group and 117 in the traditional group). The incidence of overall major and minor complications, pneumonia, extubation failure, and reintubation was lower in the positive-pressure group than in the traditional group, with statistical significance for noninferiority both in the per protocol (P < .001) and intention-to-treat (P < .001) analyses. The lower incidence of major complications found in the positive-pressure group reached statistical significance for the superiority comparison, both in per protocol (P = .03) and intention-to-treat (P = .049) analyses. No statistically significant differences were found in the superiority comparison for overall complications, minor complications, pneumonia, extubation failure, and reintubation. CONCLUSIONS: Positive pressure was safe and noninferior to traditional extubation methods. Furthermore, positive pressure has shown to be superior in terms of a lower incidence of major complications. (ClinicalTrials.gov registration NCT03174509.).

Diverse genetic-driven immune landscapes dictate tumor progression through distinct mechanisms.

Multiple immune-cell types can infiltrate tumors and promote progression and metastasis through different mechanisms, including immunosuppression. How distinct genetic alterations in tumors affect the composition of the immune landscape is currently unclear. Here, we characterized the immune-cell composition of prostate cancers driven by the loss of the critical tumor suppressor gene Pten, either alone or in combination with the loss of Trp53, Zbtb7a or Pml. We observed a striking quantitative and qualitative heterogeneity that was directly dependent on the specific genetic events in the tumor and ranged from 'cold', noninflamed tumors to massively infiltrated landscapes-results with important therapeutic implications. Further, we showed these qualitative differences in transcriptomic analysis of human prostate cancer samples. These data suggest that patient stratification on the basis of integrated genotypic-immunophenotypic analyses may be necessary for successful clinical trials and tailored precision immunological therapies.

A circular twist on microRNA regulation.

Circular RNAs (circRNAs) are a novel class of RNA whose physiological function has yet to be investigated. A recent publication in Science provides the first evidence of the biological relevance of a circRNA in an in vivo model and unveils an unexpected twist on their crosstalk with miRNAs.

PRDM15 safeguards naive pluripotency by transcriptionally regulating WNT and MAPK-ERK signaling.

The transcriptional network acting downstream of LIF, WNT and MAPK-ERK to stabilize mouse embryonic stem cells (ESCs) in their naive state has been extensively characterized. However, the upstream factors regulating these three signaling pathways remain largely uncharted. PR-domain-containing proteins (PRDMs) are zinc-finger sequence-specific chromatin factors that have essential roles in embryonic development and cell fate decisions. Here we characterize the transcriptional regulator PRDM15, which acts independently of PRDM14 to regulate the naive state of mouse ESCs. Mechanistically, PRDM15 modulates WNT and MAPK-ERK signaling by directly promoting the expression of Rspo1 (R-spondin1) and Spry1 (Sprouty1). Consistent with these findings, CRISPR-Cas9-mediated disruption of PRDM15-binding sites in the Rspo1 and Spry1 promoters recapitulates PRDM15 depletion, both in terms of local chromatin organization and the transcriptional modulation of these genes. Collectively, our findings uncover an essential role for PRDM15 as a chromatin factor that modulates the transcription of upstream regulators of WNT and MAPK-ERK signaling to safeguard naive pluripotency.

Capacidad estructural, recursos humanos tecnológicos y requerimientos de ventilación mecánica en 58 unidades de cuidados intensivos en argentina durante la pandemia por SARS-CoV-2. Estudio SATICOVID-19 / Structural capacity, technological human resources and mechanical ventilation requirements in 58 intensive care units in Argentina during the SARS-CoV-2 pandemic. A SATICOVID-19 Study

Resumen Durante la pandemia por SARS-CoV-2 hubo un marcado requerimiento de camas de cuidados críticos, insumos y profesionales entrenados para asistir a pacientes con insuficiencia respiratoria grave. La Sociedad Argentina de Terapia Intensiva (SATI) diseñó un estudio para caracterizar estos aspectos en las Unidades de Cuidados Intensivos (UCIs). Estudio multicéntrico, de cohorte prospectiva; las UCIs participantes completaron un formulario al final del estudio (31/10/2020) sobre características hospitalarias, número de camas de áreas críticas pre- e intra-pandemia, incorporación de profesionales, insumos y recursos tecnológicos, y carga de trabajo. Participaron 58 UCIs; 28(48%) de Provincia de Buenos Aires, 22(38%) de Ciudad Autónoma de Bue nos Aires, 10(17%) de otras; 31(53%) UCIs pertenecían al sector público; 23(47%) al privado-seguridad social. En 35/58(60%) hospitales las camas de cuidados críticos aumentaron de 902 a 1575(75%); 37% en UCI y 63% principalmente en Unidad Coronaria y Emergencias-shock room. En 41/55(75%) UCIs se incorporó personal: 27(49%) médicos/as (70% intensivistas), 36(65%) enfermeros/as, 28(51%) kinesiólogos/as, 20(36%) personal de limpieza, y 1(2%) otros/as; 96% de las UCIS reportaron disponer de respiradores suficientes, y 95%, insumos y EPP suficientes. De todos los pacientes en ventilación mecánica invasiva, 55% [43-64] presentaron COVID-19. Se requirió oxigenoterapia como soporte no invasivo en 14% [8-24] de los ingresos por COVID-19. Se registró una importante expansión de las áreas críticas operativas, secundariamente al aumento de camas, personal, y adecuada disponibilidad de respiradores e insumos esenciales. La carga de la enfermedad crítica por COVID-19 fue intensa, constituyendo más de la mitad de los pacientes en ventilación mecánica.

Abstract During the SARS-CoV-2 pandemic, there was a marked requirement for critical care beds, supplies and trained professionals to assist patients with severe respiratory failure. The Argentine Society of Intensive Care (SATI) designed a study to characterize these aspects in intensive care units (ICUs). Multicenter, prospective cohort study; the participating ICUs completed a form at the end of the study (31/10/2020) on hospital characteristics, number of beds in pre- and intra-pandemic critical areas, incorporation of professionals, technological resources, and workload. Fifty-eight ICUs participated; 28(48%) were located in Buenos Aires Province, 22(38%) in Buenos Aires Autonomous City and 10 (17%) in other provinces; 31 (53%) of UCIs belonged to the public sector; 23 (47%) to the private-social security. In 35/58 (60%) of the hospitals critical care beds increased from 902 to 1575 (75%), 37% in ICU and 63% mainly in Coronary Care Unit and Emergency-shock room. In 41/55 (75%) UCIs, staff were incorporated: 27(49%) physicians (70% intensivists), 36 (65%) nurses, 28 (51%) respiratory therapists, 20(36%) cleaning staff, and 1(2%) others. A 96% of the ICUS reported having sufficient ventilators and 95% enough sup plies and PPE. Of all patients on invasive mechanical ventilation, 55% [43-64] had COVID-19. Oxygen therapy was required as noninvasive support in 14% [8-24] of COVID-19 admissions. There was a significant expansion of critical operational areas, secondary to the increase in beds, staff, and adequate availability of ventilators and essential supplies. The burden of critical illness from COVID-19 was intense, with more than half of patients on mechanical ventilation.

Antisense oligonucleotide-mediated MDM4 exon 6 skipping impairs tumor growth.

MDM4 is a promising target for cancer therapy, as it is undetectable in most normal adult tissues but often upregulated in cancer cells to dampen p53 tumor-suppressor function. The mechanisms that underlie MDM4 upregulation in cancer cells are largely unknown. Here, we have shown that this key oncogenic event mainly depends on a specific alternative splicing switch. We determined that while a nonsense-mediated, decay-targeted isoform of MDM4 (MDM4-S) is produced in normal adult tissues as a result of exon 6 skipping, enhanced exon 6 inclusion leads to expression of full-length MDM4 in a large number of human cancers. Although this alternative splicing event is likely regulated by multiple splicing factors, we identified the SRSF3 oncoprotein as a key enhancer of exon 6 inclusion. In multiple human melanoma cell lines and in melanoma patient-derived xenograft (PDX) mouse models, antisense oligonucleotide-mediated (ASO-mediated) skipping of exon 6 decreased MDM4 abundance, inhibited melanoma growth, and enhanced sensitivity to MAPK-targeting therapeutics. Additionally, ASO-based MDM4 targeting reduced diffuse large B cell lymphoma PDX growth. As full-length MDM4 is enhanced in multiple human tumors, our data indicate that this strategy is applicable to a wide range of tumor types. We conclude that enhanced MDM4 exon 6 inclusion is a common oncogenic event and has potential as a clinically compatible therapeutic target.