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1.
Conserv Biol ; 37(3): e14093, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37021387

RESUMEN

Conservation decisions are invariably made with incomplete data on species' distributions, habitats, and threats, but frameworks for allocating conservation investments rarely account for missing data. We examined how explicit consideration of missing data can boost return on investment in ecosystem restoration, focusing on the challenge of restoring aquatic ecosystem connectivity by removing dams and road crossings from rivers. A novel way of integrating the presence of unmapped barriers into a barrier optimization model was developed and applied to the U.S. state of Maine to maximize expected habitat gain for migratory fish. Failing to account for unmapped barriers during prioritization led to nearly 50% lower habitat gain than was anticipated using a conventional barrier optimization approach. Explicitly acknowledging that data are incomplete during project selection, however, boosted expected habitat gains by 20-273% on average, depending on the true number of unmapped barriers. Importantly, these gains occurred without additional data. Simply acknowledging that some barriers were unmapped, regardless of their precise number and location, improved conservation outcomes. Given incomplete data on ecosystems worldwide, our results demonstrate the value of accounting for data shortcomings during project selection.


Incremento de la restauración de la conectividad a gran escala de los ríos mediantze la planeación de la presencia de barreras sin registro Resumen Las decisiones de conservación se toman con datos incompletos de la distribución, hábitat y amenazas de las especies, pero los marcos para asignar fondos de conservación rara veces lo consideran. Analizamos cómo la consideración explícita de los datos faltantes puede incrementar la rentabilidad de la inversión en la restauración de ecosistemas. Nos enfocamos en el reto que es la restauración de la conectividad entre ecosistemas acuáticos mediante la eliminación de presas y cruces de carreteras en los ríos. Desarrollamos y aplicamos una forma novedosa de integrar la presencia de las barreras sin registro dentro de un modelo de optimización de barreras en el estado de Maine (Estados Unidos) para maximizar la ganancia esperada de hábitat para los peces migratorios. La omisión de las barreras sin registro durante la priorización resultó en una ganancia de hábitat casi 50% menor a la anticipada cuando se usó una estrategia convencional de optimización de barreras. Sin embargo, el reconocimiento explícito de los datos incompletos durante la selección del proyecto incrementó la ganancia esperada de hábitat en un promedio del 20-273%, dependiendo del número real de barreras sin registro. Estas ganancias ocurrieron sin datos adicionales. Los resultados de conservación aumentaron con tan sólo el reconocimiento de que algunas barreras no estaban registradas, sin importar el número y ubicación precisos, Ya que hay datos incompletos para todos los ecosistemas a nivel mundial, nuestros resultados demuestran lo importante que es considerar la carencia de datos durante la selección de proyectos.


Asunto(s)
Ecosistema , Ríos , Animales , Conservación de los Recursos Naturales/métodos , Peces
2.
J Immigr Minor Health ; 25(1): 96-103, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35441972

RESUMEN

BACKGROUND: Migration-flows pose the risk of poliovirus reintroduction from endemic countries to Greece. This study aims to evaluate serologic-immunity/vaccination against poliomyelitis in newly-arriving migrant children. METHODS: Demographic-immunisation data and blood-serum were obtained from migrants 1-14years-old, referred to a hospital-clinic in Athens-Greece within three months from arrival. Immunity to polioviruses-1-3 was determined by serum-neutralizing-antibodies(WHO guidelines). Titers ≥ 1:8 were considered positive. RESULTS: From 9/2010 to 9/2013, 274 children(150 refugees/124 immigrants), mean age 7.1years-old, were enrolled. Only 57(20.8%) of them presented with vaccination-records. Children originated mainly from Asia(n = 198), Eastern Europe(n = 28), Middle East(n = 24) and Africa(n = 24) with 160(58.4%) from polio-endemic-countries(Afghanistan-112(40.8%), Pakistan-24(8.8%) and India-24(8.8%)). Seropositivity against polio-1-2&3 was 84.3%, 86.1% and 74.5%, respectively. Immigrants, had higher seroprotective rates against polioviruses-1-2&3 than refugees(polio-1:p = 0.002;polio-2:p = 0.004,polio-3:p < 0.001). Seronegativity to 1PVs-2PVs and all three polio serotypes was found in 37(13.5%),12 (4.4%), and 30 children(10.9%) respectively. Increasing number of vaccine-doses, and younger-age, were positively-associated with seropositivity. DISCUSSION: A remarkable fraction of newly-arrived migrant-children were seronegative to one or more polioviruses.


Asunto(s)
Poliomielitis , Poliovirus , Migrantes , Humanos , Lactante , Niño , Grecia/epidemiología , Poliomielitis/prevención & control , Poliomielitis/epidemiología , Vacunación , Pakistán
3.
Front Behav Neurosci ; 15: 722796, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34421557

RESUMEN

The ability to form associations between different stimuli in the environment to guide adaptive behavior is a central element of learning processes, from perceptual learning in humans to Pavlovian conditioning in animals. Like so, classical conditioning paradigms that test direct associations between low salience sensory stimuli and high salience motivational reinforcers are extremely informative. However, a large part of everyday learning cannot be solely explained by direct conditioning mechanisms - this includes to a great extent associations between individual sensory stimuli, carrying low or null immediate motivational value. This type of associative learning is often described as incidental learning and can be captured in animal models through sensory preconditioning procedures. Here we summarize the evolution of research on incidental and mediated learning, overview the brain systems involved and describe evidence for the role of cannabinoid receptors in such higher-order learning tasks. This evidence favors a number of contemporary hypotheses concerning the participation of the endocannabinoid system in psychosis and psychotic experiences and provides a conceptual framework for understanding how the use of cannabinoid drugs can lead to altered perceptive states.

4.
Addict Biol ; 26(3): e12940, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32744799

RESUMEN

Synthetic cannabinoids have emerged as novel psychoactive substances with damaging consequences for public health. They exhibit high affinity at the cannabinoid type-1 (CB1 ) receptor and produce similar and often more potent effects as other CB1 receptor agonists. However, we are still far from a complete pharmacological understanding of these compounds. In this study, by using behavioral, molecular, pharmacological, and electrophysiological approaches, we aimed at characterizing several in vitro and in vivo pharmacological effects of the synthetic cannabinoid MMB-Fubinaca (also known as AMB-Fubinaca or FUB-AMB), a particular synthetic cannabinoid. MMB-Fubinaca stimulates CB1 receptor-mediated functional coupling to G-proteins in mouse and human brain preparations in a similar manner as the CB1 receptor agonist WIN55,512-2 but with a much greater potency. Both drugs similarly activate the CB1 receptor-dependent extracellular signal-regulated kinase (ERK) pathway. Notably, in vivo administration of MMB-Fubinaca in mice induced greater behavioral and electrophysiological effects in male than in female mice in a CB1 receptor-dependent manner. Overall, these data provide a solid pharmacological profiling of the effects of MMB-Fubinaca and important information about the mechanisms of action underlying its harmful impact in humans. At the same time, they reinforce the significant sexual dimorphism of cannabinoid actions, which will have to be taken into account in future animal and clinical studies.


Asunto(s)
Encéfalo/metabolismo , Cannabinoides/farmacología , Indazoles/farmacología , Valina/análogos & derivados , Animales , Encéfalo/patología , Femenino , Células HEK293 , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismo , Factores Sexuales , Valina/farmacología
5.
Nature ; 583(7817): 603-608, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32641832

RESUMEN

Astrocytes take up glucose from the bloodstream to provide energy to the brain, thereby allowing neuronal activity and behavioural responses1-5. By contrast, astrocytes are under neuronal control through specific neurotransmitter receptors5-7. However, whether the activation of astroglial receptors can directly regulate cellular glucose metabolism to eventually modulate behavioural responses is unclear. Here we show that activation of mouse astroglial type-1 cannabinoid receptors associated with mitochondrial membranes (mtCB1) hampers the metabolism of glucose and the production of lactate in the brain, resulting in altered neuronal functions and, in turn, impaired behavioural responses in social interaction assays. Specifically, activation of astroglial mtCB1 receptors reduces the phosphorylation of the mitochondrial complex I subunit NDUFS4, which decreases the stability and activity of complex I. This leads to a reduction in the generation of reactive oxygen species by astrocytes and affects the glycolytic production of lactate through the hypoxia-inducible factor 1 pathway, eventually resulting in neuronal redox stress and impairment of behavioural responses in social interaction assays. Genetic and pharmacological correction of each of these effects abolishes the effect of cannabinoid treatment on the observed behaviour. These findings suggest that mtCB1 receptor signalling can directly regulate astroglial glucose metabolism to fine-tune neuronal activity and behaviour in mice.


Asunto(s)
Astrocitos/metabolismo , Metabolismo Energético , Glucosa/metabolismo , Mitocondrias/metabolismo , Receptor Cannabinoide CB1/metabolismo , Animales , Astrocitos/citología , Astrocitos/efectos de los fármacos , Agonistas de Receptores de Cannabinoides/farmacología , Células Cultivadas , Dronabinol/farmacología , Complejo I de Transporte de Electrón/química , Complejo I de Transporte de Electrón/metabolismo , Metabolismo Energético/efectos de los fármacos , Glucólisis/efectos de los fármacos , Humanos , Factor 1 Inducible por Hipoxia/metabolismo , Ácido Láctico/metabolismo , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Oxidación-Reducción , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Receptor Cannabinoide CB1/agonistas , Conducta Social
6.
Neuron ; 99(6): 1247-1259.e7, 2018 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-30174119

RESUMEN

By priming brain circuits, associations between low-salience stimuli often guide future behavioral choices through a process known as mediated or inferred learning. However, the precise neurobiological mechanisms of these incidental associations are largely unknown. Using sensory preconditioning procedures, we show that type 1 cannabinoid receptors (CB1R) in hippocampal GABAergic neurons are necessary and sufficient for mediated but not direct learning. Deletion and re-expression of CB1R in hippocampal GABAergic neurons abolishes and rescues mediated learning, respectively. Interestingly, paired presentations of low-salience sensory cues induce a specific protein synthesis-dependent enhancement of hippocampal CB1R expression and facilitate long-term synaptic plasticity at inhibitory synapses. CB1R blockade or chemogenetic manipulations of hippocampal GABAergic neurons upon preconditioning affect incidental associations, as revealed by impaired mediated learning. Thus, CB1R-dependent control of inhibitory hippocampal neurotransmission mediates incidental associations, allowing future associative inference, a fundamental process for everyday life, which is altered in major neuropsychiatric diseases. VIDEO ABSTRACT.


Asunto(s)
Hipocampo/metabolismo , Depresión Sináptica a Largo Plazo/fisiología , Receptor Cannabinoide CB1/metabolismo , Sinapsis/fisiología , Animales , Neuronas GABAérgicas/metabolismo , Ratones , Plasticidad Neuronal/fisiología , Transmisión Sináptica/fisiología
7.
Bio Protoc ; 8(7): e2789, 2018 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-34286012

RESUMEN

Animal models are an important tool for studying neuropsychiatric disorders. However, a major challenge for researchers working with laboratory rodents is trying to reproduce 'core' symptoms of complex human disorders such as schizophrenia. Despite this challenge, however, it is still conceivable to use animal models designed to reproduce some of the disease's 'endo-phenotypes'. One example is the prepulse inhibition (PPI) of the startle reflex. PPI is a form of startle plasticity and is characterized by a normal reduction in startle magnitude that occurs when an intense startling stimulus (or pulse) is preceded by a weaker pre-stimulus (or prepulse). The PPI paradigm is commonly used to evaluate sensorimotor gating and it has been described in numerous species including humans and rodents. Deficits in PPI have been observed in subjects with schizophrenia and other neuropsychiatric diseases, as well as in established animal models of these disorders. The PPI paradigm is therefore largely used to explore genetic and neurobiological mechanisms underlying the sensorimotor gating phenotypes found in these disorders. Thus, it is necessary to set up reliable and reproducible protocols to study PPI in mice.

8.
Health Promot Pract ; 18(5): 636-644, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-27807196

RESUMEN

Nursery schools serve as reservoirs of transmission of infectious diseases, and teachers should be able to implement and monitor hygiene measures to prevent them. The aim of the present study was to assess the compliance of nursery school teachers on promoting preventive interventions and to identify associated factors, during the novel H1N1 influenza pandemic. A secondary objective was to evaluate their knowledge and vaccination status regarding the novel virus. A cross-sectional study was performed, with the use of a predesigned anonymous, questionnaire, and distributed to all public nursery teachers of Athens, Greece. General etiquette practices were highly acceptable to over 92% of teachers. Those with longer teaching experience promoted simple preventive measures, such as hand washing and use of hand sanitizer, more often while older children were more likely to familiarize with them. However, teachers presented inadequate knowledge concerning the novel virus and their vaccination rates with the pandemic vaccine were unacceptably low (1.1%). Our study showed that promotion of simple preventive measures is feasible and may contribute to the prevention of outbreaks in nursery schools, although knowledge gaps and fear concerning the pandemic vaccine highlight communication issues.


Asunto(s)
Control de Infecciones/organización & administración , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana/prevención & control , Escuelas de Párvulos/organización & administración , Adulto , Anciano , Estudios Transversales , Femenino , Grecia , Desinfección de las Manos/métodos , Humanos , Vacunas contra la Influenza/administración & dosificación , Persona de Mediana Edad
9.
J Acoust Soc Am ; 139(3): 1241-51, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27036260

RESUMEN

Amplitude modulation (AM) may be an important factor for the perceived annoyance of wind turbine noise (WTN). Two AM types, typically referred to as "normal AM" (NAM) and "other AM" (OAM), characterize WTN AM, OAM corresponding to having intermittent periods with larger AM depth in lower frequency regions than NAM. The extent to which AM depth, frequency, and type affect WTN annoyance remains uncertain. Moreover, the temporal variations of WTN AM have often not been considered. Here, realistic stimuli accounting for such temporal variations were synthesized such that AM depth, frequency, and type, while determined from real on-site recordings, could be varied systematically. Listening tests with both original and synthesized stimuli showed that a reduction in mean AM depth across the spectrum led to a significant decrease in annoyance. When the spectrotemporal characteristics of the original far-field stimuli and the temporal AM variations were taken into account, the effect of AM frequency remained limited and the presence of intermittent OAM periods did not affect annoyance. These findings suggest that, at a given overall level, the AM depth of NAM periods is the most crucial AM parameter for WTN annoyance.

10.
Artículo en Inglés | MEDLINE | ID: mdl-15093962

RESUMEN

UNLABELLED: The aim of the present study was to search for differences between subtypes of major depression with the use of single photon emission tomography. MATERIALS AND METHODS: Fifty (50) patients aged 21-60 years suffering from Major Depression according to DSM-IV took part in the study. The SCAN v 2.0 was used to assist clinical diagnosis. The psychometric assessment included the HDRS, the HAS, the GAF, the Newcastle scales and the Diagnostic Melancholia Scale (DMS). Single Photon Emission Computerized Tomography (HMPAO SPECT) was used to assess regional cerebral blood flow. The methods of analysis included chi-square test, ANCOVA, and Discriminant Function Analysis. RESULTS: Forty one (82%) depressed patients had abnormal SPECT findings. The most consistent finding in all patients across all subtypes was a global brain hypoperfusion, which did not include the frontal lobes. The most impressive finding was the relative increase of right frontal lobe perfusion in atypicals, in contrast to the relative decrease of perfusion in both the melancholic and the 'undifferentiated' patients in that particular region. The reverse was true for the right occipital lobe. CONCLUSION: The results of the current study provide support for the old hypothesis on the existence of two distinct types of depression, characterized by different underlying psychopathologies, but also provide strong evidence for a neurobiological abnormality underlying atypical depression, the subtype closer to the old concept of 'neurotic' depression, which was considered to be psychological or reactive in origin.


Asunto(s)
Circulación Cerebrovascular/fisiología , Trastorno Depresivo Mayor/fisiopatología , Adulto , Química Encefálica , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Radiofármacos , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único
11.
Neuropsychobiology ; 49(1): 42-52, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14730200

RESUMEN

Suicide is a major problem for psychiatry. Depression is the most common mental disorder related to suicidal behavior. The present study aimed at investigating the relationship between the symptomatology related to death, dying, and suicide and neurobiological factors in depressed patients. Fifty patients aged 21-60 years suffering from major depression were investigated. Schedules for Clinical Assessment in Neuropsychiatry version 2.0 and the International Personality Disorder Examination were used to assist the clinical diagnosis. The psychometric assessment included the Hamilton Depression Rating Scale, the Hamilton Anxiety Scale, the 1965 and 1971 Newcastle Depression Diagnostic Scales, the Diagnostic Melancholia Scale, the General Assessment of Functioning Scale, and the Personality Deviance Scale. Psychophysiological methods included electro-oculogram, flash electroretinogram under photopic and scotopic conditions, and pattern-reversal visual evoked potentials. Biological markers included the 1-mg dexamethasone suppression test, the 30-mg dexfenfluramine challenge test, and brain (99m)Tc-HMPAO SPECT. Statistical analysis included one-, two-, and three-way Manova and Mancova and the Scheffé test as post hoc test. Patients without thoughts of death had higher self-confidence levels and less overdependency on others and intropunitiveness. The suicidal patients had a significantly prolonged pattern-reversal visual evoked potential latency in comparison with the other patients. The findings of this were related to the status of the patient at the time of the interview but not to his/her history. They also provide neurobiological data to support the need for a combined presence of self-directed aggression and a higher arousal level or disinhibition of self-directed aggressive thoughts in order for a patient to become suicidal. Further study is needed to test whether psychophysiological methods, which are noninvasive and easy to perform, are of value in the therapeutic planning and monitoring of responses.


Asunto(s)
Muerte , Trastorno Depresivo Mayor/psicología , Intento de Suicidio , Pensamiento , Adulto , Análisis de Varianza , Biomarcadores/sangre , Trastorno Depresivo Mayor/sangre , Trastorno Depresivo Mayor/fisiopatología , Electrooculografía/métodos , Electrorretinografía , Potenciales Evocados Visuales , Femenino , Humanos , Hidrocortisona/sangre , Entrevista Psicológica , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Inventario de Personalidad , Escalas de Valoración Psiquiátrica , Psicometría , Psicofisiología , Serotonina/metabolismo , Tomografía Computarizada de Emisión de Fotón Único
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