Dysregulation in contextual processing is believed to affect several forms of psychopathology, such as post-traumatic stress disorder (PTSD). The dentate gyrus (DG), a subregion of the hippocampus, ...is thought to be an important brain region for disambiguating new experiences from prior experiences. Noradrenergic (NE) neurons in the locus coeruleus (LC) are more tonically active during stressful events and send dense projections to the DG, yet an understanding of their function in DG-dependent contextual discrimination has not been established. Here, we isolate a key function of the LC-NE-DG circuit in contextual aversive generalization using selective manipulations and in vivo single-cell calcium imaging. We report that activation of LC-NE neurons and terminal activity results in contextual generalization. We found that these effects required β-adrenergic-mediated modulation of hilar interneurons to ultimately promote aversive generalization, suggesting that disruption of noradrenergic tone may serve as an important avenue for treating stress-induced disorders.
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•Bidirectional manipulation of LCNE-DG circuits alters aversive contextual learning•DG neuronal ensembles shift context selectivity during aversive contextual conditioning•Chemogenetic LCNE excitation during conditioning impairs DG ensemble dynamics•β-adrenergic and GABA hilar interneuron modulation disrupt contextual learning
Seo et al. implicate a locus coeruleus to dentate gyrus noradrenergic circuit in modulation of aversive contextual processing. Disrupted contextual processing occurs in several psychopathologies, including post-traumatic stress disorder (PTSD). Elucidating the role of noradrenergic modulation of behavior can yield more effective treatments for stress disorders.
Aim
There is a lack of studies related to the frequency, phenomenology, and associated features of catatonic syndrome in patients with anti‐NMDA receptor encephalitis (ANMDARE). This study aimed to ...measure the frequency of catatonia in this condition and to delineate its particular symptoms.
Methods
A prospective study was done with all inpatients who fulfilled the criteria of definite ANMDARE admitted to the National Institute of Neurology and Neurosurgery of Mexico from January 2014 to September 2018. The Bush–Francis Catatonia Rating Scale and Braünig Catatonia Rating Scale were administered at admission.
Results
Fifty‐eight patients were included and catatonia was diagnosed in 41 of these patients (70.6%). Immobility, staring, mutism, and posturing were the most frequent catatonic signs. Catatonia was associated with delirium, hallucinations, psychomotor agitation, generalized electroencephalography dysfunction, and previous use of antipsychotics. Mortality was present in 10% of the total sample; it was associated with status epilepticus, and was less frequent in the catatonia group. After immunotherapy, all cases showed a complete recovery from catatonic signs.
Conclusion
This systematic assessment of catatonic syndrome shows that it is a frequent feature in patients with ANMDARE as part of a clinical pattern that includes delirium, psychomotor agitation, and hallucinations. The lack of recognition of this pattern may be a source of diagnostic and therapeutic errors, as most physicians associate catatonia with schizophrenia and affective disorders.
La historiadora Patricia Nelson Limerick, hace tres décadas, pre-sentó en sus escritos una explicación diferente, usando conscientemente la palabra “conquista” para describir la entrada de los ...euro-estadou-nidenses en el Oeste Americano a mediados del siglo XIX. Limerick destacó el conflicto inherente a la colonización estadounidense del norte de México tanto como la competencia sobre la tierra y el trabajo que tuvo un fuerte componente racial.Aunque Limerick nos dio una explicación general de este proceso, voy a considerar la conquista estadounidense de México desde un punto de vista diferente, con el objetivo de situar la consiguiente formación de los mexicano-estadounidenses como un grupo racial. La equívoca y común consideración de los mexicanos como un nuevo grupo étnico en Estados Unidos ensombrece el legado de la colonización estadounidense en la conformación de la experiencia mexicano-estadounidense. La evi-dencia revela que la colonización estadounidense en el norte de México debería ser comprendida como el momento en el que los mexicano-esta-dounidenses se constituyeron por vez primera en un grupo racial.
The general goal of this study consists of analyzing the influence of different types of human services in the quality of life of their nested users. Several multilevel models were proposed to test ...for significant differences not only in the overall quality of life score, but also in each of the eight core domains. Participants included 11,624 users of social and human services and the assessment quality of life instrument was the GENCAT Scale. Variables that were studied in the different models were gender, age, and diagnostic group (elderly, intellectual disability, physical disability, mental health problems, and chemical dependency) at the individual user level (level 1: individual), while type of services—in terms of the main population addressed by their supports (i. e. the aforementioned groups)—was studied at service level (level 2: organizational). In order to explain differences, individual characteristics were introduced first, types of services were introduced next, and finally joint individual and service variables were introduced in a single model. The main results of this study were that personal and organizational variables exhibited a different level of influence on users’quality of life; and also that the type of services significantly influenced the quality of life of its users. The results of this study lead to practical implications for services providing support to these diagnostic groups, especially for those interested in managing, assessing, and improving quality of life related personal outcomes at the user level as well as quality enhancement at the organizational level.
Research on resource partitioning in plant–pollinator mutualistic systems is mainly concentrated at the levels of species and communities, whereas differences between males and females are typically ...ignored. Nevertheless, pollinators often show large sexual differences in behaviour and morphology, which may lead to sex‐specific patterns of resource use with the potential to differentially affect plant reproduction and diversification.
We investigated variation in behavioural and morphological traits between sexes of hummingbird species as potential mechanisms underlying sex‐specific flower resource use in ecological communities. To do so, we compiled a dataset of plant–hummingbird interactions based on pollen loads for 31 hummingbird species from 13 localities across the Americas, complemented by data on territorial behaviour (territorial or non‐territorial) and morphological traits (bill length, bill curvature, wing length and body mass).
We assessed the extent of intersexual differences in niche breadth and niche overlap in floral resource use across hummingbird species. Then, we tested whether floral niche breadth and overlap between sexes are associated with sexual dimorphism in behavioural or morphological traits of hummingbird species while accounting for evolutionary relatedness among the species.
We found striking differences in patterns of floral resource use between sex. Females had a broader floral niche breadth and were more dissimilar in the plant species visited with respect to males of the same species, resulting in a high level of resource partitioning between sexes. We found that both territoriality and morphological traits were related to sex‐specific resource use by hummingbird species. Notably, niche overlap between sexes was greater for territorial than non‐territorial species, and moreover, niche overlap was negatively associated with sexual dimorphism in bill curvature across hummingbird species.
These results reveal the importance of behavioural and morphological traits of hummingbird species in sex‐specific resource use and that resource partitioning by sex is likely to be an important mechanism to reduce intersexual competition in hummingbirds. These findings highlight the need for better understanding the putative role of intersexual variation in shaping patterns of interactions and plant reproduction in ecological communities.
Resumen
La investigación sobre la partición de recursos en los sistemas mutualistas planta‐polinizador se concentra principalmente en los niveles de especies y comunidades, mientras que las diferencias entre machos y hembras suelen ser ignoradas. Sin embargo, los polinizadores suelen mostrar grandes diferencias sexuales en su comportamiento y morfología, lo que puede dar lugar a patrones específicos de uso de recursos para cada sexo con el potencial de afectar de forma diferencial la reproducción y la diversificación de las plantas.
Se estudió la variación en los rasgos de comportamiento y morfológicos entre sexos de las especies de colibríes como posibles mecanismos que explican el uso de recursos florales específicos para cada sexo en las comunidades ecológicas. Para ello, se recopiló un conjunto de datos de interacciones planta‐colibrí con base en las cargas de polen de 31 especies de colibríes de 13 localidades en las Américas, además de datos sobre su comportamiento territorial (territorial o no territorial) y rasgos morfológicos (longitud y curvatura del pico, longitud del ala y masa corporal).
Se evaluaron las diferencias intersexuales en la amplitud y el solapamiento del nicho en el uso de los recursos florales para las distintas especies de colibríes. Posteriormente, se comprobó si la amplitud del nicho floral y el solapamiento entre sexos están asociados con el dimorfismo sexual en los rasgos de comportamiento o morfológicos de las especies de colibríes, teniendo en cuenta el parentesco evolutivo entre las especies.
Se encontraron diferencias notables en los patrones de uso de los recursos florales entre sexos. Las hembras presentaron una mayor amplitud de nicho floral y fueron más disímiles en las especies de plantas visitadas con respecto a los machos de la misma especie, lo que resultó en un alto nivel de partición de recursos entre los sexos. Se encontró que tanto la territorialidad como los rasgos morfológicos están relacionados con el uso de recursos específicos por sexo en las especies de colibríes. En particular, el solapamiento de nicho entre sexos fue mayor para las especies territoriales que para las no territoriales y, además, el solapamiento de nicho se asoció negativamente con el dimorfismo sexual en la curvatura del pico en las especies de colibríes.
Estos resultados revelan la importancia de los rasgos conductuales y morfológicos de las especies de colibríes en el uso de recursos según el sexo y que la partición de recursos entre sexos es probablemente un mecanismo importante para reducir la competencia intersexual en los colibríes. Estos resultados ponen de manifiesto la necesidad de comprender mejor el rol que tiene la variación intersexual en los patrones de interacción y en la reproducción de las plantas en las comunidades ecológicas.
Research on resource partitioning in plant–pollinator mutualistic systems is mainly concentrated at the levels of species and communities, whereas differences between males and females are typically ignored. Discover why behaviour and morphology are important factors influencing sex‐specific patterns in resource use in hummingbird species across the Americas. Photo: Cauã Galeazzi de Menezes.
Multidrug-resistant tuberculosis (MDR-TB), caused by drug-resistant strains of Mycobacterium tuberculosis, is an increasingly serious problem worldwide. Here we examined a data set of whole-genome ...sequences from 5,310 M. tuberculosis isolates from five continents. Despite the great diversity of these isolates with respect to geographical point of isolation, genetic background and drug resistance, the patterns for the emergence of drug resistance were conserved globally. We have identified harbinger mutations that often precede multidrug resistance. In particular, the katG mutation encoding p.Ser315Thr, which confers resistance to isoniazid, overwhelmingly arose before mutations that conferred rifampicin resistance across all of the lineages, geographical regions and time periods. Therefore, molecular diagnostics that include markers for rifampicin resistance alone will be insufficient to identify pre-MDR strains. Incorporating knowledge of polymorphisms that occur before the emergence of multidrug resistance, particularly katG p.Ser315Thr, into molecular diagnostics should enable targeted treatment of patients with pre-MDR-TB to prevent further development of MDR-TB.
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