Time of injection determines the effect of alpha-MSH antiserum on DA neurons in psychological stress

Male rats were subjected to "psychological stress" which consisted in 10 sec footshock on the first day followed 24 hr later by a 10 sec stay in the experimental chamber without shock. Intravenous antiserum against alpha-MSH markedly changed the functional state of mesencephalic and hypothalamic DA neurons (assessed by histochemical microfluorimetry) when administered before the second session but not when given before the first session. These observations reveal an interesting parallelism in the temporal characteristics of the effects of alpha-MSH on avoidance behavior and central DA systems.

The Ionotropic receptors IR21a and IR25a mediate cool sensing in Drosophila.

Animals rely on highly sensitive thermoreceptors to seek out optimal temperatures, but the molecular mechanisms of thermosensing are not well understood. The Dorsal Organ Cool Cells (DOCCs) of the Drosophila larva are a set of exceptionally thermosensitive neurons critical for larval cool avoidance. Here, we show that DOCC cool-sensing is mediated by Ionotropic Receptors (IRs), a family of sensory receptors widely studied in invertebrate chemical sensing. We find that two IRs, IR21a and IR25a, are required to mediate DOCC responses to cooling and are required for cool avoidance behavior. Furthermore, we find that ectopic expression of IR21a can confer cool-responsiveness in an Ir25a-dependent manner, suggesting an instructive role for IR21a in thermosensing. Together, these data show that IR family receptors can function together to mediate thermosensation of exquisite sensitivity.

Attachment and temperament in early childhood; implications for later behavior problems.

In the context of a French validation study, the Child Behavior Checklist (CBCL) was administered to more than 3000 French speaking mothers of 5-year-old children. Scores were factor-analyzed. Principal components analysis revealed four dimensions: externalizing and internalizing behavior problems, immaturity and somatoform disorders. Another sample of 40 mothers participated in a longitudinal study, filling in the CBCL when their children were 5 years old. These children had been observed previously in the Strange Situation (SSP) at 21 months. Several dichotomous variables derived from the SSP (e.g. secure versus insecure, proximal versus distal interaction with the mother, avoidant behavior) have been used as predictors of the four dimensions extracted from the CBCL. Hierarchical regressions showed that proximal behaviors with the mother, which reflect temperamental characteristics independently of the quality of attachment, predicted internalizing problems, whereas avoidance of the mother, or insecure-avoidant attachment, predicted internalizing as well as externalizing problems at 5 years of age. These results show that attachment and temperament, as assessed by the SSP, may each have specific implications for later behavior problems.

Experimental evidence of inbreeding avoidance in the hermaphroditic snail Physa acuta

Inbreeding depression should select for inbreeding avoidance behaviours. Here we test this hypothesis in two populations of the simultaneous hermaphroditic freshwater snail Physa acuta. We recorded the copulatory behaviour of 288 pairs of sib-mates, non-kin mates from the same population, or non-kin mates from two different populations. We find that kin discriminatory behaviours exist in this species, exclusively expressed by individuals playing the female role. We discuss the relevance of our finding in the context of the evolution of recognition systems and the consequences of such a behaviour in natural populations.

Inbreeding avoidance through kin recognition: choosy females boost male dispersal.

Inbreeding avoidance is predicted to induce sex biases in dispersal. But which sex should disperse? In polygynous species, females pay higher costs to inbreeding and thus might be expected to disperse more, but empirical evidence consistently reveals male biases. Here, we show that theoretical expectations change drastically if females are allowed to avoid inbreeding via kin recognition. At high inbreeding loads, females should prefer immigrants over residents, thereby boosting male dispersal. At lower inbreeding loads, by contrast, inclusive fitness benefits should induce females to prefer relatives, thereby promoting male philopatry. This result points to disruptive effects of sexual selection. The inbreeding load that females are ready to accept is surprisingly high. In absence of search costs, females should prefer related partners as long as delta<r/(1+r) where r is relatedness and delta is the fecundity loss relative to an outbred mating. This amounts to fitness losses up to one-fifth for a half-sib mating and one-third for a full-sib mating, which lie in the upper range of inbreeding depression values currently reported in natural populations. The observation of active inbreeding avoidance in a polygynous species thus suggests that inbreeding depression exceeds this threshold in the species under scrutiny or that inbred matings at least partly forfeit other mating opportunities for males. Our model also shows that female choosiness should decline rapidly with search costs, stemming from, for example, reproductive delays. Species under strong time constraints on reproduction should thus be tolerant of inbreeding.

La dépendance à l'égard de l'environnement lors de lésions cérébrales: conduites d'imitation, de préhension et d'utilisation [Environmental dependence in brain lesions: imitative behavior, prehension and utilization].

This paper reviews the literature on clinical signs such as imitation behavior, grasp reaction, manipulation of tools, utilization behavior, environmental dependency, hyperlexia, hypergraphia and echolalia. Some aspects of this semiology are of special interest because they refer to essential notions such as free-will and autonomy.

Molecular variation at a candidate gene implicated in the regulation of fire ant social behavior

The fire ant Solenopsis invicta and its close relatives display an important social polymorphism involving differences in colony queen number. Colonies are headed by either a single reproductive queen (monogyne form) or multiple queens (polygyne form). This variation in social organization is associated with variation at the gene Gp-9, with monogyne colonies harboring only B-like allelic variants and polygyne colonies always containing b-like variants as well. We describe naturally occurring variation at Gp-9 in fire ants based on 185 full-length sequences, 136 of which were obtained from S. invicta collected over much of its native range. While there is little overall differentiation between most of the numerous alleles observed, a surprising amount is found in the coding regions of the gene, with such substitutions usually causing amino acid replacements. This elevated coding-region variation may result from a lack of negative selection acting to constrain amino acid replacements over much of the protein, different mutation rates or biases in coding and non-coding sequences, negative selection acting with greater strength on non-coding than coding regions, and/or positive selection acting on the protein. Formal selection analyses provide evidence that the latter force played an important role in the basal b-like lineages coincident with the emergence of polygyny. While our data set reveals considerable paraphyly and polyphyly of S. invicta sequences with respect to those of other fire ant species, the b-like alleles of the socially polymorphic species are monophyletic. An expanded analysis of colonies containing alleles of this clade confirmed the invariant link between their presence and expression of polygyny. Finally, our discovery of several unique alleles bearing various combinations of b-like and B-like codons allows us to conclude that no single b-like residue is completely predictive of polygyne behavior and, thus, potentially causally involved in its expression. Rather, all three typical b-like residues appear to be necessary.

The evolution of inbred social systems in spiders and other organisms: from short-term gains to long-term evolutionary dead-ends?

The question of why some social systems have evolved close inbreeding is particularly intriguing given expected short- and long-term negative effects of this breeding system. Using social spiders as a case study, we quantitatively show that the potential costs of avoiding inbreeding through dispersal and solitary living could have outweighed the costs of inbreeding depression in the origin of inbred spider sociality. We further review the evidence that despite being favored in the short term, inbred spider sociality may constitute in the long run an evolutionary dead end. We also review other cases, such as the naked mole rats and some bark and ambrosia beetles, mites, psocids, thrips, parasitic ants, and termites, in which inbreeding and sociality are associated and the evidence for and against this breeding system being, in general, an evolutionary dead end.

Peri-insular hemispherotomy: potential pitfalls and avoidance of complications.

Techniques for cerebral hemispherectomy have progressively evolved towards more disconnection and less excision over the last 50 years. Peri-insular hemispherotomy (PIH), as described by the senior author, has the maximal ratio of disconnection to excision among all procedures for hemispheric epilepsy. In this study, we focus on surgical complications and intraoperative anatomical observations during PIH over the last 10 years. Based on this experience, the procedure has undergone some modifications, which we detail herein.

Behavior of endogenous tumor-associated macrophages assessed in vivo using a functionalized nanoparticle.

Tumor-associated macrophages (TAMs) invade the tumor stroma in many cancers, yet their role is incompletely understood. To visualize and better understand these critical cells in tumor progression, we screened a portfolio of rationally selected, injectable agents to image endogenous TAMs ubiquitously in three different cancer models (colon carcinoma, lung adenocarcinoma, and soft tissue sarcoma). AMTA680, a functionally derivatized magneto-fluorescent nanoparticle, labeled a subset of myeloid cells with an "M2" macrophage phenotype, whereas other neighboring cells, including tumor cells and a variety of other leukocytes, remained unlabeled. We further show that AMTA680-labeled endogenous TAMs are not altered and can be tracked noninvasively at different resolutions and using various imaging modalities, e.g., fluorescence molecular tomography, magnetic resonance imaging, and multiphoton and confocal intravital microscopy. Quantitative assessment of TAM distribution and activity in vivo identified that these cells cluster in delimited foci within tumors, show relatively low motility, and extend cytoplasmic protrusions for prolonged physical interactions with neighboring tumor cells. Noninvasive imaging can also be used to monitor TAM-depleting regimen quantitatively. Thus, AMTA680 or related cell-targeting agents represent appropriate injectable vehicles for in vivo analysis of the tumor microenvironment.

Emotional behavior in acute stroke: the Lausanne emotion in stroke study.

OBJECTIVE: To study emotional behaviors in an acute stroke population. BACKGROUND: Alterations in emotional behavior after stroke have been recently recognized, but little attention has been paid to these changes in the very acute phase of stroke. METHODS: Adult patients presenting with acute stroke were prospectively recruited and studied. We validated the Emotional Behavior Index (EBI), a 38-item scale designed to evaluate behavioral aspects of sadness, aggressiveness, disinhibition, adaptation, passivity, indifference, and denial. Clinical, historical, and imaging (computed tomography/magnetic resonance imaging) data were obtained on each subject through our Stroke Registry. Statistical analysis was performed with both univariate and multivariate tests. RESULTS: Of the 254 patients, 40% showed sadness, 49% passivity, 17% aggressiveness, 53% indifference, 76% disinhibition, 18% lack of adaptation, and 44% denial reactions. Several significant correlations were identified. Sadness was correlated with a personal history of alcohol abuse (r = P < 0.037), female gender (r = P < 0.028), and hemorrhagic nature of the stroke (r = P < 0.063). Aggressiveness was correlated with a personal history of depression (r = P < 0.046) and hemorrhage (r = P < 0.06). Denial was correlated with male gender (r = P < 0.035) and hemorrhagic lesions (r = P < 0.05). Emotional behavior did not correlate with either neurologic impairment or lesion localization, but there was an association between hemorrhage and aggressive behavior (P < 0.001), lack of adaptation (r = P < 0.015), indifference (r = P < 0.018), and denial (r = P < 0.045). CONCLUSIONS: Systematic observations of acute emotional behaviors after stroke suggest that emotional alterations are independent of mood and physical status and should be considered as a separate consequence of stroke.

Catastrophic reaction in acute stroke: a reflex behavior in aphasic patients.

Twelve patients with a catastrophic reaction (CR) (an outburst of frustration, depression, and anger when confronted with a task) were identified in a prospective cohort population (n = 326) with first-ever stroke admitted within 48 hours from onset. The authors' findings suggest that CR is a rare though not exceptional phenomenon in acute stroke and is associated with nonfluent aphasias and left opercular lesions. CR, poststroke depression, and emotionalism are distinct but related disorders.

Neither Bad Apple nor Bad Barrel: How the Societal Context Impacts Unethical Behavior in Organizations

Every time another corporate scandal captures media headlines, the 'bad apple vs. bad barrel' discussion starts anew. Yet this debate overlooks the influence of the broader societal context on organizational behavior. In this article, we argue that misbehaviors of organizations (the 'barrels') and their members (the 'apples') cannot be addressed properly without a clear understanding of their broader context (the 'larder'). Whereas previously, a strong societal framework dampened the practical application of the Homo economicus concept (business actors as perfectly rational and egocentric utility-maximizing agents without any moral concern), specialization, individualization and globalization led to a business world disembedded from broader societal norms. This emancipated business world promotes a literal interpretation of Homo economicus among business organizations and their members. Consequently, we argue that the first step toward 'healthier' apples and barrels is to sanitize the larder, that is, adapt the framework in which organizations and their members evolve.Chaque fois qu'un nouveau scandale fait la une des médias, la question de savoir si le problème se situe au niveau des individus (des 'pommes isolées') ou au niveau des organisations (les 'caisses de pommes') refait surface. Ce débat tend néanmoins à sous-estimer l'influence du contexte sociétal plus large sur le comportement dans les organisations. Dans cet article, nous soutenons l'idée que les scandales éthiques dans les organisations ou parmi leurs membres ne peuvent être compris correctement sans une vision plus précise de leur contexte plus large (la 'cave à pommes'). Si dans le passé un contexte sociétal fort permettait d'adoucir les applications pratiques de l'Homo economicus (qui considère l'acteur économique comme un agent parfaitement rationnel et égocentrique cherchant à maximiser son utilité sans réflexion morale), l'individualisation et la globalisation ont conduit à un monde économique désencastré et déconnecté des normes sociales plus larges. Ce monde économique autonome promouvoit une interprétation littérale de l'Homo economicus parmi les entreprises et leurs employés. Il en résulte que le premier pas vers des pommes moins pourries passe par un assainissement de la cave, c'est-à-dire l'adoption d'un cadre socio-normatif qui permet un recadrage du contexte dans lequel les organisations économiques et leurs acteurs agissent.