The centrosome protein AKNA regulates neurogenesis via microtubule organization.

The expansion of brain size is accompanied by a relative enlargement of the subventricular zone during development. Epithelial-like neural stem cells divide in the ventricular zone at the ventricles of the embryonic brain, self-renew and generate basal progenitors1 that delaminate and settle in the subventricular zone in enlarged brain regions2. The length of time that cells stay in the subventricular zone is essential for controlling further amplification and fate determination. Here we show that the interphase centrosome protein AKNA has a key role in this process. AKNA localizes at the subdistal appendages of the mother centriole in specific subtypes of neural stem cells, and in almost all basal progenitors. This protein is necessary and sufficient to organize centrosomal microtubules, and promote their nucleation and growth. These features of AKNA are important for mediating the delamination process in the formation of the subventricular zone. Moreover, AKNA regulates the exit from the subventricular zone, which reveals the pivotal role of centrosomal microtubule organization in enabling cells to both enter and remain in the subventricular zone. The epithelial-to-mesenchymal transition is also regulated by AKNA in other epithelial cells, demonstrating its general importance for the control of cell delamination.

Dual diagnosis among medical residents: a systematic review. / Diagnóstico dual en médicos residentes: una revisión sistemática.

The post-graduate period as a resident doctor (MIR, in Spanish) is usually associated with high emotional distress due to new professional demands and to other psychosocial factors. The objective of this study is to determine the characteristics of dual diagnosis among MIRs. A systematic review was carried out in MEDLINE (PubMed), Web of Science and Google Scholar databases, selecting articles published in English and Spanish between 1984 and 2017. A total of 2,415 articles were obtained: 2,276 were excluded by their title, 105 by the abstract and 17 after a complete review of the article; 17 papers were finally included. The prevalence of depressive symptoms among MIRs ranges from 10.2% to 70%, while the prevalence of anxious symptoms varies from 13.2% to 33.9%, from 6.7% to 25% reported suicidal ideation, 20% hazardous drinking, 2%-13.4% self-prescribed psychotropics, and 2.7%-14% used other drugs. Most studies present important methodological limitations, thus complicating adequate understanding of the phenomenon. High variations in prevalence data are related to differences in the psychometric scales and to disparity in diagnosis criteria, among other limitations. However, most studies report that alcohol and drug use is correlated with severe distress among MIRs. More research is needed to ascertain the nature of dual diagnosis in this professional group in order to effectively prevent and treat its serious consequences.

El período de preparación como médico residente (en español, MIR) suele asociarse a una elevada sobrecarga emocional tanto por las nuevas exigencias profesionales como por otros factores psicosociales. El objetivo de este estudio es conocer las características del diagnóstico dual en los MIRs. Se llevó a cabo una revisión sistemática de las bases de datos MEDLINE (PubMed), Web of Science y Google Scholar, seleccionando artículos publicados en inglés y español entre 1984 y 2017. Se obtuvieron 2.415 artículos: se excluyeron 2.276 por título, 105 por el contenido del resumen y 17 por el contenido del artículo. En la revisión final se incluyeron 17 artículos. La prevalencia de clínica depresiva varía del 10,2% al 70%, de ansiedad entre 13,2% y 33,9%, de ideación suicida entre 6,7% y 25% mientras que el consumo de riesgo de alcohol se encuentra aproximadamente en torno al 20%, entre 2% y 13,4% se auto-prescriben medicamentos psicótropos y del 2,7% al 14% consumen otras sustancias. La mayoría de los estudios analizados adolecen de limitaciones metodológicas importantes lo que dificulta una adecuada comprensión del fenómeno. Las variaciones en las cifras de prevalencia tienen que ver con la disparidad de escalas y de criterios diagnósticos empleados, entre otros factores. Aún así, los estudios muestran que el consumo de alcohol y/u otras sustancias se correlacionan positivamente con el malestar emocional en los MIRs. Se hace necesario mejorar el conocimiento del diagnóstico dual en este grupo profesional para que se puedan prevenir y tratar sus consecuencias de manera más eficaz.

Phenotypic integration and modularity drives skull shape divergence in the Arctic fox (Vulpes lagopus) from the Commander Islands.

Phenotypic integration and modularity influence morphological disparity and evolvability. However, studies addressing how morphological integration and modularity change for long periods of genetic isolation are scarce. Here, we investigate patterns of phenotypic integration and modularity in the skull of phenotypically and genetically distinct populations of the Artic fox (Vulpes lagopus) from the Commander Islands of the Aleutian belt (i.e. Bering and Mednyi) that were isolated ca 10 000 years by ice-free waters of the Bering sea. We use three-dimensional geometric morphometrics to quantify the strength of modularity and integration from inter-individual variation (static) and from fluctuating asymmetry (random developmental variation) in both island populations compared to the mainland population (i.e. Chukotka) and we investigated how changes in morphological integration and modularity affect disparity and the directionality of trait divergence. Our results indicate a decrease in morphological integration concomitant to an increase in disparity at a developmental level, from mainland to the smallest and farthest population of Mednyi. However, phenotypic integration is higher in both island populations accompanied by a reduction in disparity compared to the population of mainland at a static level. This higher integration may have favoured morphological adaptive changes towards specific feeding behaviours related to the extreme environmental settings of islands. Our study demonstrates how shifts in phenotypic integration and modularity can facilitate phenotypic evolvability at the intraspecific level that may lead to lineage divergence at macroevolutioanry scales.

Long-term prognostic value of peak exercise echocardiogram in patients hospitalized with acute chest pain.

INTRODUCTION: Peak exercise echocardiogram (EEcho) has shown reasonable sensitivity and specificity in detecting significant coronary artery disease (CAD). The objective was to evaluate the prognostic value of EEcho in patients hospitalized for acute chest pain (CP) and its additional prognostic information regarding exercise electrocardiogram test (EECG). METHODS: Prospective observational study performed between May 2011 and September 2013, including 250 patients consecutively admitted for acute CP with normal cardiac biomarkers and nondiagnostic electrocardiogram. All patients were prospectively followed for 1 year, and major adverse cardiovascular events (MACE) were recorded: cardiac death, nonfatal myocardial infarction (MI), or angina with coronary revascularization. RESULTS: EEcho was positive in 16%. Patients with positive EEcho had a higher incidence of hypertension and higher TIMI risk score, showing significant CAD in 66%. We observed contradictory results (EECG-EEcho) in 20%. Patients with positive EEcho and negative EECG had significant CAD in the 66%, and patients undergoing coronary angiography with negative EEcho and positive EECG did not show significant coronary artery disease. Only positive EEcho (P<.001, HR 0.169; 95% CI, 0.088-0.250) and atrial fibrillation (P<.025, HR 0.125; 95% CI, 0.016-0.233) were independently associated with MACE during follow-up. In patients with negative EEcho, the presence of MACE was 2%. CONCLUSIONS: EEcho in patients hospitalized for acute chest pain presents good ability to diagnose acute coronary syndrome, while providing additional information when combined with an EECG in up to 20% of cases. Moreover, a negative EEcho in this cohort seems to provide prognostic information beyond the acute event to predict long-term MACE.

A critical role for Sox9 in notch-induced astrogliogenesis and stem cell maintenance.

Notch signaling is a key regulator of cell-fate decisions and is essential for proper neuroectodermal development. There, it favors the formation of ectoderm, promotes maintenance of neural stem cells, inhibits differentiation into neurons, and commits neural progenitors to a glial fate. In this report, we explore downstream effects of Notch important for astroglial differentiation. Transient activation of Notch1 during early stages of neuroectodermal differentiation of embryonic stem cells resulted in an increase of neural stem cells, a reduction in neurons, an induction of astroglial cell differentiation, and an induction of neural crest (NC) development. Transient or continuous activation of Notch1 during neuroectodermal differentiation led to upregulation of Sox9 expression. Knockdown of the Notch1-induced Sox9 expression reversed Notch1-induced astroglial cell differentiation, increase in neural stem cells, and the decrease in neurons, whereas the Notch1 effects on NC development were hardly affected by knockdown of Sox9 expression. These findings reveal a critical role for Notch-mediated upregulation of Sox9 in a select set of neural lineage determination steps controlled by Notch.

Vaccine-carditis study: Spanish multicenter registry of inflammatory heart disease after COVID-19 vaccination.

INTRODUCTION AND OBJECTIVES: Vaccines against SARS-CoV-2 have been a major scientific and medical achievement in the control of the COVID-19 pandemic. However, very infrequent cases of inflammatory heart disease have been described as adverse events, leading to uncertainty in the scientific community and in the general population. METHODS: The Vaccine-Carditis Registry has included all cases of myocarditis and pericarditis diagnosed within 30 days after COVID-19 vaccination since August 1, 2021 in 29 centers throughout the Spanish territory. The definitions of myocarditis (probable or confirmed) and pericarditis followed the consensus of the Centers for Disease Control and the Clinical Practice Guidelines of the European Society of Cardiology. A comprehensive analysis of clinical characteristics and 3-month evolution is presented. RESULTS: From August 1, 2021, to March 10, 2022, 139 cases of myocarditis or pericarditis were recorded (81.3% male, median age 28 years). Most cases were detected in the 1st week after administration of an mRNA vaccine, the majority after the second dose. The most common presentation was mixed inflammatory disease (myocarditis and pericarditis). 11% had left ventricular systolic dysfunction, 4% had right ventricular systolic dysfunction, and 21% had pericardial effusion. In cardiac magnetic resonance studies, left ventricular inferolateral involvement was the most frequent pattern (58%). More than 90% of cases had a benign clinical course. After a 3-month follow-up, the incidence of adverse events was 12.78% (1.44% mortality). CONCLUSIONS: In our setting, inflammatory heart disease after vaccination against SARS-CoV-2 predominantly affects young men in the 1st week after the second dose of RNA-m vaccine and presents a favorable clinical course in most cases.

Centrosomal microtubule nucleation regulates radial migration of projection neurons independently of polarization in the developing brain.

Cortical projection neurons polarize and form an axon while migrating radially. Even though these dynamic processes are closely interwoven, they are regulated separately-the neurons terminate their migration when reaching their destination, the cortical plate, but continue to grow their axons. Here, we show that in rodents, the centrosome distinguishes these processes. Newly developed molecular tools modulating centrosomal microtubule nucleation combined with in vivo imaging uncovered that dysregulation of centrosomal microtubule nucleation abrogated radial migration without affecting axon formation. Tightly regulated centrosomal microtubule nucleation was required for periodic formation of the cytoplasmic dilation at the leading process, which is essential for radial migration. The microtubule nucleating factor γ-tubulin decreased at neuronal centrosomes during the migratory phase. As distinct microtubule networks drive neuronal polarization and radial migration, this provides insight into how neuronal migratory defects occur without largely affecting axonal tracts in human developmental cortical dysgeneses, caused by mutations in γ-tubulin.

Centrosome heterogeneity in stem cells regulates cell diversity.

Stem cells are at the source of creating cellular diversity. Multiple mechanisms, including basic cell biological processes, regulate their fate. The centrosome is at the core of many stem cell functions and recent work highlights the association of distinct proteins at the centrosome in stem cell differentiation. As showcased by a novel centrosome protein regulating neural stem cell differentiation, it is timely to review the heterogeneity of the centrosome at protein and RNA levels and how this impacts their function in stem and progenitor cells. Together with evidence for heterogeneity of other organelles so far considered as similar between cells, we call for exploring the cell type-specific composition of organelles as a way to expand protein function in development with relevance to regenerative medicine.

Blood stem cell PU.1 upregulation is a consequence of differentiation without fast autoregulation.

Transcription factors (TFs) regulate cell fates, and their expression must be tightly regulated. Autoregulation is assumed to regulate many TFs' own expression to control cell fates. Here, we manipulate and quantify the (auto)regulation of PU.1, a TF controlling hematopoietic stem and progenitor cells (HSPCs), and correlate it to their future fates. We generate transgenic mice allowing both inducible activation of PU.1 and noninvasive quantification of endogenous PU.1 protein expression. The quantified HSPC PU.1 dynamics show that PU.1 up-regulation occurs as a consequence of hematopoietic differentiation independently of direct fast autoregulation. In contrast, inflammatory signaling induces fast PU.1 up-regulation, which does not require PU.1 expression or its binding to its own autoregulatory enhancer. However, the increased PU.1 levels induced by inflammatory signaling cannot be sustained via autoregulation after removal of the signaling stimulus. We conclude that PU.1 overexpression induces HSC differentiation before PU.1 up-regulation, only later generating cell types with intrinsically higher PU.1.

Characteristics of resident physicians accessing a specialised mental health service: a retrospective study.

OBJECTIVES: Little is known about resident physicians being treated at physician health programmes around the world despite the fact that it is a highly demanding training period. This study aims to describe the profiles of resident physicians accessing a specialised mental health service in Spain over a 20-year period and to compare them to consultant-grade physicians. DESIGN: Retrospective observational study. SETTING: Medical records of the Galatea Care Programme for Sick Physicians. PARTICIPANTS: 1846 physicians registered at the Barcelona Medical Council-Association and admitted to the programme from January 1998 to December 2018. PRIMARY AND SECONDARY OUTCOME MEASURES: Number of admissions, sociodemographic and clinical variables, including medical specialty, main diagnosis and need of hospitalisation. RESULTS: Residents accounted for 18.1% (n=335) of the sample and admissions increased over the years. Most residents (n=311; 94.5%) and consultant-grade physicians (n=1391; 92.8%) were self-referred. The most common specialty among residents was family medicine (n=107; 31.9%), followed by internal medicine (n=18; 5.4%), paediatrics (n=14; 4.2%), psychiatry (n=13; 3.9%) and anaesthesiology (n=13; 3.9%). Residents, regardless of year of training, mainly asked for help because of adjustment (n=131; 39.1%), affective (n=77; 23%), anxiety disorders (n=40; 18.8%) and addictions (n=19; 5.7%). There were no significant differences between groups in the main diagnosis and in the variables related to need of hospitalisation. The percentage of residents accessing the programme was higher than in the reference population registered at the Barcelona Medical Council-Association (18.1% vs 7.6%; z=7.2, p<0.001) as was the percentage of family medicine residents (31.9% vs 19.6%; z=5.7, p<0.001). CONCLUSIONS: Residents are more likely than consultant-grade physicians to seek help when suffering from mental disorders. Local primary prevention actions since the beginning of their training period and having access to a well-known highly reliable programme may partly explain these findings.

A Novel GATA2 Protein Reporter Mouse Reveals Hematopoietic Progenitor Cell Types.

The transcription factor (TF) GATA2 plays a key role in organ development and cell fate control in the central nervous, urogenital, respiratory, and reproductive systems, and in primitive and definitive hematopoiesis. Here, we generate a knockin protein reporter mouse line expressing a GATA2VENUS fusion from the endogenous Gata2 genomic locus, with correct expression and localization of GATA2VENUS in different organs. GATA2VENUS expression is heterogeneous in different hematopoietic stem and progenitor cell populations (HSPCs), identifies functionally distinct subsets, and suggests a novel monocyte and mast cell lineage bifurcation point. GATA2 levels further correlate with proliferation and lineage outcome of hematopoietic progenitors. The GATA2VENUS mouse line improves the identification of specific live cell types during embryonic and adult development and will be crucial for analyzing GATA2 protein dynamics in TF networks.

Preanalytical mistakes in samples from primary care patients.

BACKGROUND: Preanalytical mistakes (PAMs) in samples usually led to rejection upon arrival to the clinical laboratory. However, PAMs might not always be detected and result in clinical problems. Thus, PAMs should be minimized. We detected PAMs in samples from Primary Health Care Centres (PHCC) served by our central laboratory. Thus, the goal of this study was to describe the number and types of PAMs, and to suggest some strategies for improvement. METHODS: The presence of PAMs, as sample rejection criteria, in samples submitted from PHCC to our laboratory during October and November 2007 was retrospectively analysed. RESULTS: Overall, 3885 PAMs (7.4%) were detected from 52,669 samples for blood analyses. This included missed samples (n=1763; 45.4% of all PAMs, 3.3% of all samples), haemolysed samples (n=1408; 36.2% and 2.7%, respectively), coagulated samples (n=391; 10% and 0.7%, respectively), incorrect sample volume (n=110; 2.8% and 0.2%, respectively), and others (n=213; 5.5% and 0.4%, respectively). For urine samples (n=18,852), 1567 of the samples were missing (8.3%). CONCLUSIONS: We found the proportion of PAMs in blood and urine samples to be 3-fold higher than that reported in the literature. Therefore, strategies for improvement directed towards the staff involved, as well as an exhaustive audit of preanalytical process are needed. To attain this goal, we first implemented a continued education programme, financed by our Regional Health Service and focused in Primary Care Nurses.

Neuronal differentiation induces SNORD115 expression and is accompanied by post-transcriptional changes of serotonin receptor 2c mRNA.

The serotonin neurotransmitter system is widespread in the brain and implicated in modulation of neuronal responses to other neurotransmitters. Among 14 serotonin receptor subtypes, 5-HT2cR plays a pivotal role in controlling neuronal network excitability. Serotonergic activity conveyed through receptor 5-HT2cR is regulated post-transcriptionally via two mechanisms, alternative splicing and A-to-I RNA editing. Brain-specific small nucleolar RNA SNORD115 harbours a phylogenetically conserved 18-nucleotide antisense element with perfect complementarity to the region of 5ht2c primary transcript that undergoes post-transcriptional changes. Previous 5ht2c minigene studies have implicated SNORD115 in fine-tuning of both post-transcriptional events. We monitored post-transcriptional changes of endogenous 5ht2c transcripts during neuronal differentiation. Both SNORD115 and 5ht2c were upregulated upon neuronal commitment. We detected increased 5ht2c alternative exon Vb inclusion already at the stage of neuronal progenitors, and more extensive A-to-I editing of non-targeted sites A and B compared to adjacent adenosines at sites E, C and D throughout differentiation. As the extent of editing is known to positively correlate with exon Vb usage while it reduces receptor functionality, our data support the model where SNORD115 directly promotes alternative exon inclusion without the requirement for conversion of key adenosines to inosines, thereby favouring production of full-length receptor isoforms with higher potency.

Hypoxia-induced arterial differentiation requires adrenomedullin and notch signaling.

Hypoxia (low oxygen) and Notch signaling are 2 important regulators of vascular development, but how they interact in controlling the choice between arterial and venous fates for endothelial cells during vasculogenesis is less well understood. In this report, we show that hypoxia and Notch signaling intersect in promotion of arterial differentiation. Hypoxia upregulated expression of the Notch ligand Dll4 and increased Notch signaling in a process requiring the vasoactive hormone adrenomedullin. Notch signaling also upregulated Dll4 expression, leading to a positive feedback loop sustaining Dll4 expression and Notch signaling. In addition, hypoxia-mediated upregulation of the arterial marker genes Depp, connexin40 (Gja5), Cxcr4, and Hey1 required Notch signaling. In conclusion, the data reveal an intricate interaction between hypoxia and Notch signaling in the control of endothelial cell differentiation, including a hypoxia/adrenomedullin/Dll4 axis that initiates Notch signaling and a requirement for Notch signaling to effectuate hypoxia-mediated induction of the arterial differentiation program.