Palaeontological Virtual Congress: A new way to make science

On the first month of 2018, one of the authors (VDC) of this preface had an interesting idea: to hold a virtual congress. At first, he did not know of the existence of this kind of congress, but a quick internet search showed him that there were some examples in the fields of medicine and veterinary medicine; however, it had never been done in palaeontology. For that reason, with the help of other co-workers from the Universitat de València, Museo Paleontológico de Alpuente and Museu Valencià d’Historia Natural, we decided to undertake this adventure.Fil: Crespo Roures, Vicente Daniel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Museo Paleontológico de Alpuente; España. Museu Valencia d'Història Natural; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Manzanares, Esther. Universidad de Valencia; España. Institut Cavanilles de Biodiversitat i Biologia Evolutiva; Españ

Microfilament-coordinated adhesion dynamics drives single cell migration and shapes whole tissues [version 1; Referees:4:approved]

Cell adhesion to the substratum and/or other cells is a crucial step of cell migration. While essential in the case of solitary migrating cells (for example, immune cells), it becomes particularly important in collective cell migration, in which cells maintain contact with their neighbors while moving directionally. Adhesive coordination is paramount in physiological contexts (for example, during organogenesis) but also in pathology (for example, tumor metastasis). In this review, we address the need for a coordinated regulation of cell-cell and cell-matrix adhesions during collective cell migration. We emphasize the role of the actin cytoskeleton as an intracellular integrator of cadherin- and integrin-based adhesions and the emerging role of mechanics in the maintenance, reinforcement, and turnover of adhesive contacts. Recent advances in understanding the mechanical regulation of several components of cadherin and integrin adhesions allow us to revisit the adhesive clutch hypothesis that controls the degree of adhesive engagement during protrusion. Finally, we provide a brief overview of the major impact of these discoveries when using more physiological three-dimensional models of single and collective cell migration

A regulatory motif in nonmuscle myosin II-B regulates its role in migratory front-back polarity

In this study, we show that the role of nonmuscle myosin II (NMII)-B in front–back migratory cell polarity is controlled by a short stretch of amino acids containing five serines (1935–1941). This motif resides near the junction between the C terminus helical and nonhelical tail domains. Removal of this motif inhibited NMII-B assembly, whereas its insertion into NMII-A endowed an NMII-B–like ability to generate large actomyosin bundles that determine the rear of the cell. Phosphomimetic mutation of the five serines also inhibited NMII-B assembly, rendering it unable to support front–back polarization. Mass spectrometric analysis showed that several of these serines are phosphorylated in live cells. Single-site mutagenesis showed that serine 1935 is a major regulatory site of NMII-B function. These data reveal a novel regulatory mechanism of NMII in polarized migrating cells by identifying a key molecular determinant that confers NMII isoform functional specificityThis work is supported by grants SAF2011-24953 from MINECO, FP7 Marie Curie CIG-293719 from the EU, CIVP16A1831 from the Ramon Areces Foundation (M. Vicente-Manzanares), GM 23244 (A.R. Horwitz), GM037537 (D.F. Hunt), and the Cell Migration Consortium U54 GM64346 (A.R. Horwitz and D.F. Hunt). M. Vicente-Manzanares is an investigator from the Ramón y Cajal Program (RYC-2010-06094)

Fibroblast migration in 3D is controlled by haptotaxis in a non-muscle myosin II-dependent manner

Cell migration in 3D is a key process in many physiological and pathological processes. Although valuable knowledge has been accumulated through analysis of various 2D models, some of these insights are not directly applicable to migration in 3D. In this study, we have confined biomimetic hydrogels within microfluidic platforms in the presence of a chemoattractant (platelet-derived growth fac- tor-BB). We have characterized the migratory responses of human fibroblasts within them, particularly focusing on the role of non-muscle myosin II. Our results indicate a prominent role for myosin II in the integration of chemo- tactic and haptotactic migratory responses of fibroblasts in 3D confined environments

Perioral aerosol sequestration suction device effectively reduces biological cross-contamination in dental procedures

Background: The infection risk during dental procedures is a common concern for dental professionals which has increased due to coronavirus (SARS-CoV-2) pandemic. The development of devices to specifically mitigate cross-contamination by droplet/splatter is crucial to stop infection transmission. This study assesses the effectiveness of a perioral suction device (Oral BioFilter, OBF®) to reduce biological contamination spread during dental procedures. Methods: Forty patients were randomized 1:1 to standard professional dental hygiene treatment with OBF® or not. Adenosine Triphosphate (ATP) bioluminiscence assay was used to evaluate the spread of potential contaminants. The total number of Relative Light Units (RLU) from key dental operatory locations: operator's face-shield, back of the surgical operator's-gloves, patient's safety-goggles, and instrumental table, were measured. Percentage contamination reductions between control and OBF® were compared. Results: For the whole dental environment, the RLUs reduction (300) being 100% on the surfaces closer to the patient's mouth and decreasing to 70% on instrumental table. In contrast, the higher failure percentage in the OBF®-group was found on the patient's googles (40%), while the operator face-shield showed an absence of contamination. Conclusion: OBF® device has shown efficacy to reduce biological droplet/splatter cross-contamination using ATP-bioluminiscence assay during dental procedures. Nevertheless, for maximum safety, its use must be combined with standard protective gear such as goggles, face shield and surgical glove

Morfología de los conductos radiculares de premolares superiores e inferiores

El propósito de este estudio fue caracterizar la anatomía de los conductos radiculares de dientes premolares superiores e inferiores provenientes de pacientes españoles. Fueron seleccionados 200 dientes premolares permanentes sometidos a diafanización. Para el estudio de los conductos radiculares se empleó la clasificación de Vertucci. La incidencia de conducto tipo I (un conducto) para los primeros premolares superiores fue de 5.88%, mientras que un 88.22% presentó dos conductos (de tipo II a tipo VI). Sólo el 5.88% de los primeros premolares superiores fueron tipo VIII (tres conductos). En los segundos premolares superiores, la incidencia de un conducto (tipo I) fue de 39.65%, y el 60.31% presentaron dos conductos (de tipo II a tipo VII). La incidencia de un conducto (tipo I) fue de 68.18% para los primeros premolares inferiores, y un 31.8% presentó dos conductos (de tipo II a tipo V). En los segundos premolares inferiores, la incidencia de tipo I (un conducto) fue de 73.91%, mientras que el 26.08% presentó dos conductos (de tipo IV a V). Salvo en el caso del segundo premolar inferior, nuestros resultados coincidieron con los de trabajos previos hechos en otras poblaciones

In vivo antihypertensive mechanism of lactoferrin-derived peptides: Reversion of angiotensin I- and angiotensin II-induced hypertension in Wistar rats

Novel peptides with antihypertensive effects in SHR rats have previously been identified in lactoferrin (LF) hydrolysates. To investigate their in vivo antihypertensive mechanism, we have assessed the blood pressure lowering effects of two of these LF-derived peptides (RPYL and DPYKLRP) in Wistar rats subjected to either angiotensin I- or angiotensin II-induced hypertension. Blood pressure was measured by the tail-cuff method, hypertension was induced by subcutaneous infusion of angiotensins, and then captopril, valsartan or LF-derived peptides orally administered. Angiotensin I- and angiotensin II-induced hypertension were reversed by captopril and valsartan, respectively. RPYL and DPYKLRP reversed angiotensin I-induced hypertension, while DPYKLRP but not RPYL produced a modest reversion of angiotensin II-elicited hypertension. Neither RPYL nor DPYKLRP modified normotension. Thus, in vivo ACE inhibition is involved in the antihypertensive effects of LF-derived peptides like RPYL and DPYKLRP, while inhibition of AT1 receptor-mediated vasoconstriction plays a less relevant role.This work was supported by grant AGL2010-21009 from ‘Ministerio de Educación y Ciencia – FEDER’, Consolider Ingenio 2010, Fun-C-Food, CSD2007-00063 and RETICS INVICTUS RD12/0014/0004 from ‘Instituto de Salud Carlos III’. A. García-Tejedor is recipient of a predoctoral fellowship from ‘Ministerio de Educación y Ciencia’ (BES-2011-044424).Peer reviewe

An antihypertensive lactoferrin hydrolysate inhibits angiotensin I-converting enzyme, modifies expression of hypertension-related genes and enhances nitric oxide production in cultured human endothelial cells

This study was aimed to explore whether an antihypertensive lactoferrin hydrolysate (LFH) can inhibit angiotensin I-converting enzyme (ACE) activity and modify the expression of genes related to hypertension in human umbilical vein endothelial cells (HUVEC). LFH induced significant inhibition of ACE activity but it did not affect ACE mRNA levels after 24 h of exposure. LFH treatment significantly affected the expression of genes encoding for proteins involved in nitric oxide pathway such as soluble guanylate cyclase 1 α3 subunit (GUCY1A3; 4.42-fold increase) and nitric oxide synthase trafficking (NOSTRIN; 2.45-fold decrease). Furthermore, expression of the PTGS2/COX-2 gene encoding prostaglandin-endoperoxide synthase 2 a key component of prostaglandin synthesis was significantly increased (2.23-fold). Moreover, NOSTRIN mRNA downregulation was consistent with reduced NOSTRIN protein expression and increased NO production observed in HUVEC. The present study reveals the complexity of the effects exerted by LFH opening avenues for the better understanding of its antihypertensive effects.This work was supported by grant AGL2010-21009 from ‘Ministerio de Educación y Ciencia – FEDER’, Consolider Ingenio 2010, Fun-C-Food, CSD2007-00063 and RETICS INVICTUS RD12/0014/0004 from ‘Instituto de Salud Carlos III’. A. García-Tejedor is recipient of a predoctoral fellowship from ‘Ministerio de Educación y Ciencia’ (BES-2011-044424).Peer reviewe