Cooperative cell motility during tandem locomotion of amoeboid cells.

Streams of migratory cells are initiated by the formation of tandem pairs of cells connected head to tail to which other cells subsequently adhere. The mechanisms regulating the transition from single to streaming cell migration remain elusive, although several molecules have been suggested to be involved. In this work, we investigate the mechanics of the locomotion ofDictyosteliumtandem pairs by analyzing the spatiotemporal evolution of their traction adhesions (TAs). We find that in migrating wild-type tandem pairs, each cell exerts traction forces on stationary sites (∼80% of the time), and the trailing cell reuses the location of the TAs of the leading cell. Both leading and trailing cells form contractile dipoles and synchronize the formation of new frontal TAs with ∼54-s time delay. Cells not expressing the lectin discoidin I or moving on discoidin I-coated substrata form fewer tandems, but the trailing cell still reuses the locations of the TAs of the leading cell, suggesting that discoidin I is not responsible for a possible chemically driven synchronization process. The migration dynamics of the tandems indicate that their TAs' reuse results from the mechanical synchronization of the leading and trailing cells' protrusions and retractions (motility cycles) aided by the cell-cell adhesions

Aproximación cartesiana a la etiopatogenia de la melancolía: el papel modulador de la glándula pineal sobre las pasiones del alma

La conceptualización de la melancolía como una corrupción de las "pasiones" (emociones o sentimientos) ha sido una constante a lo largo de la historia de la medicina y de la psicología. René Descartes dedicó su última obra publicada en vida (El Tratado de las Pasiones del Alma, 1649) a este tópico y definió las pasiones como movimientos sensibles experimentados por el alma como consecuencia de su unión con el cuerpo. El alma, en esta teoría neuropsicofisiológica, se encontraría localizada en la glándula pineal, desde donde participaría activamente dirigiendo el funcionalismo de la "maquina humana" y controlando sus disfunciones, mediante la convección de los espíritus animales. Para Descartes, los diferentes temperamentos humanos eran consecuencia de las propiedades de los espíritus animales (cantidad, consistencia y nivel de agitación). En este punto, la tristeza es considerada como una "de las seis pasiones puras del alma", que cuando no se logra corregir deriva en melancolía. Los postulados cartesianos ejercieron una gran influencia en la forma de entender la patología mental hasta el siglo XVIII

Cartesian theories on the passions, the pineal gland and the pathogenesis of affective disorders: an early forerunner

The relationship between physical and functional alterations in the pineal gland, the ‘ passions’ (emotions or feelings) and psychopathology has been a constant throughout the history of medicine. One of the most influential authors on this subject was Rene´ Descartes, who discussed it in his work The Treatise on the Passions of the Soul (1649). Descartes believed that ‘ passions’ were sensitive movements that the soul, located in the pineal gland, experienced due to its union with the body, by circulating animal spirits. Descartes described sadness as one of the six primitive passions of the soul, which leads to melancholy if not remedied. Cartesian theories had a great deal of influence on the way that mental pathologies were considered throughout the entire 17th century and during much of the 18th century, but the link between the pineal gland and psychiatric disorders it was definitively highlighted in the 20th century, with the discovery of melatonin in 1958. The recent development of a new pharmacological agent acting through melatonergic receptors (agomelatine) has confirmed the close link between the pineal gland and affective disorders

The Pharmacological Role and Clinical Applications of Antipsychotics’ Active Metabolites: Paliperidone versus Risperidone

Some antipsychotic drugs are metabolized in the liver, leading to active metabolites. These metabolites can maintain the effect of the original substrate or display different pharmacokinetic or pharmacodynamic properties, and that can be translated by a different profile of responses and interactions to clinical level. Among these is risperidone, whose active metabolite, 9-OH-risperidone, is known as paliperidone and has been marketed as such. In this review, we analyze the differential pharmacological aspects between risperidone and paliperidone, both from the pharmacokinetic (bioavailability, effect of CYP450 and P-glycoprotein, etc.) and pharmacodynamic perspectives (affinity for dopaminergic and/or serotonergic receptors, speed of dissociation from dopamine receptors, serotonin 5-HT2Areceptor occupancy>D2, etc.) as well as differential electrophysiological profile and neuroprotective role. The pharmacological differences between the two drugs could explain the differential clinical response exhibited by schizophrenic patients treated with both agents, as well as some differences in tolerability profile and drug interactions

It is Possible Find an Antidepressant with Faster Onset of Action? Ketamine: Promise or Reality?

Monoaminergic antidepressants have a delay in the onset of response that needs alternatives. Sub anesthetic doses of ketamine, a NMDA receptor antagonist, show a rapid-acting antidepressant effect in Major Depressive Disorder (MDD) and in bipolar depression, and improve suicidal ideation. However, for ketamine routinely use as antidepressant, more clinical research on the relation risks and benefits is needed to decide if ketamine is a promise or a realit

ADHD and Sport: Controversial about Treatment

$ttention-'eficit Hyperactivity Disorder (ADHD) is one of the neuropsychiatric conditions that has received most attention in the scientific literature in the last years [1], and is the most widespread problem in developmental neurology and one of the commonest reasons for neuropaediatric consultations. Нe prevalence of this disorder is generally accepted to be around 5-6% in children of school age (range 4-12%) [2]. ADHD is a chronic psychiatric disorder that is characterized by three nuclear symptoms; inattention, hyperactivity, and impulsivity. Нe predomination of one of them define the subtypes of ADHD: inattentive, hyperactivity or combine. ADHD symptoms have an adverse impact in academic, social and family relationship and also aوٴect to sport. Despite this disorder is manifest during childhood and adolescence and also can persist into adulthood, there are scarce information about the problematic of that individuals with this condition could be taking part in sports activity at all competition levels

Quo Vadis Clozapine? A Bibliometric Study of 45 Years of Research in International Context

We have carried out a bibliometric study about the international scientific publications on clozapine. We have used the EMBASE and MEDLINE databases, and we applied bibliometric indicators of production, as Price’s Law on the increase of scientific literature. We also calculated the participation index (PI) of the different countries. The bibliometric data have also been correlated with some social and health data from the 12 most productive countries in biomedicine and health sciences. In addition, 5607 original documents dealing with clozapine, published between 1970 and 2013, were downloaded. Our results state non-fulfilment of Price’s Law, with scientific production on clozapine showing linear growth (r = 0.8691, vs. r = 0.8478 after exponential adjustment). Seven of the 12 journals with the highest numbers of publications on clozapine have an Impact Factor > 2. Among the countries generating clozapine research, the most prominent is the USA (PI = 24.32), followed by the UK (PI = 6.27) and Germany (PI = 5.40). The differences among countries on clozapine research are significantly related to economic variables linked to research. The scientific interest in clozapine remains remarkable, although after the application of bibliometric indicators of production, a saturation point is evident in the growth of scientific literature on this topic