Supporting proactive planning for climate change adaptation and conservation using an attributed road-river structure dataset.

Freshwater species and their habitats, and transportation networks are at heightened risk from changing climate and are priorities for adaptation, with the sheer abundance and individuality of road-river structures complicating mitigation efforts. We present a new spatial dataset of road-river structures attributed as culverts, bridges, or fords, and use this along with data on gradient and stream order to estimate structure sensitivity and exposure in and out of special areas of conservation (SAC) and built-up areas to determine vulnerability to damage across river catchments in Wales, UK. We then assess hazard of flooding likelihood at the most vulnerable structures to determine those posing high risk of impact on roads and river-obligate species (fishes and mussels) whose persistence depends on aquatic habitat connectivity. Over 5% (624/11,680) of structures are high vulnerability and located where flooding hazard is highest, posing high risk of impact to roads and river-obligate species. We assess reliability of our approach through an on-ground survey in a river catchment supporting an SAC and more than 40% (n = 255) of high-risk structures, and show that of the subset surveyed >50% had obvious physical degradation, streambank erosion, and scouring. Our findings help us to better understand which structures pose high-risk of impact to river-obligate species and humans with increased flooding likelihood.

Emerging infectious diseases of amphibians in Poland: distribution and environmental drivers.

Emerging infectious diseases are a threat to biodiversity and have taken a large toll on amphibian populations worldwide. The chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), and the iridovirus Ranavirus (Rv), are of concern as all have contributed to amphibian declines. In central and eastern Europe, their geographical and host distributions and main environmental drivers determining prevalence are poorly known. We screened over 1000 amphibians from natural and captive populations in Poland for the presence of Bd, Bsal and Rv. In wild amphibian populations, we found that Bd is widespread, present in 46 out of 115 sampled localities as well as 2 captive colonies, and relatively common with overall prevalence at 14.4% in 9 species. We found lower prevalence of Rv at 2.4%, present in 11 out of 92 sampling sites, with a taxonomic breadth of 8 different amphibian species. Bsal infection was not detected in any individuals. In natural populations, Pelophylax esculentus and Bombina variegata accounted for 75% of all Bd infections, suggesting a major role for these 2 species as pathogen reservoirs in Central European freshwater habitats. General linear models showed that climatic as well as landscape features are associated with Bd infection in Poland. We found that higher average annual temperature constrains Bd infection, while landscapes with numerous water bodies or artificial elements (a surrogate for urbanization) increase the chances of infection. Our results show that a combination of climatic and landscape variables may drive regional and local pathogen emergence.

HERC1 Ubiquitin Ligase Is Required for Hippocampal Learning and Memory.

Mutations in the human HERC1 E3 ubiquitin ligase protein develop intellectual disability. The tambaleante (tbl) mouse carries a HERC1 mutation characterized by cerebellar ataxia due of adult cerebellar Purkinje cells death by extensive autophagy. Our previous studies demonstrated that both the neuromuscular junction and the peripheral nerve myelin sheaths are also affected in this mutant. Moreover, there are signs of dysregulated autophagy in the central nervous system in the tbl mouse, affecting spinal cord motor neurons, and pyramidal neurons of the neocortex and the hippocampal CA3 region. The tbl mutation affects associative learning, with absence of short- and long-term potentiation in the lateral amygdala, altered spinogenesis in their neurons, and a dramatic decrease in their glutamatergic input. To assess whether other brain areas engaged in learning processes might be affected by the tbl mutation, we have studied the tbl hippocampus using behavioral tests, ex vivo electrophysiological recordings, immunohistochemistry, the Golgi-Cox method and transmission electron microscopy. The tbl mice performed poorly in the novel-object recognition, T-maze and Morris water maze tests. In addition, there was a decrease in glutamatergic input while the GABAergic one remains unaltered in the hippocampal CA1 region of tbl mice, accompanied by changes in the dendritic spines, and signs of cellular damage. Moreover, the proportions of immature and mature neurons in the dentate gyrus of the tbl hippocampus differ relative to the control mice. Together, these observations demonstrate the important role of HERC1 in regulating synaptic activity during learning.

The spatial level of analysis affects the patterns of forest ecosystem services supply and their relationships.

The implementation of the Ecosystem Services (ES) framework (including supply and demand) should be based on accurate spatial assessments to make it useful for land planning or environmental management. Despite the inherent dependence of ES assessments on the spatial resolution at which they are conducted, the studies analyzing these effects on ES supply and their relationships are still scarce. To study the influence of the spatial level of analysis on ES patterns and on the relationships among different ES, we selected seven indicators representing ES supply and three variables that describe forest cover and biodiversity for Catalonia (NE Iberian Peninsula). These indicators were estimated at three different scales: local, municipality and county. Our results showed differences in the ES patterns among the levels of analysis. The higher levels (municipality/county) removed part of the local heterogeneity of the patterns observed at the local scale, particularly for ES indicators characterized by a finely grained, scattered distribution. The relationships between ES indicators were generally similar at the three levels. However, some negative relationships (potential trade-offs) that were detected at the local level changed to positive (and significant) relationships at municipality and county. Spatial autocorrelation showed similarities between patterns at local and municipality levels, but differences with county level. We conclude that the use of high-resolution spatial data is preferable whenever available, in particular when identifying hotspots or trade-offs/synergies is of primary interest. When the main objective is describing broad patterns of ES, intermediate levels (e.g., municipality) are also adequate, as they conserve many of the properties of assessments conducted at finer scales, allowing the integration of data sources and, usually, being more directly relevant for policy-making. In conclusion, our results warn against the uncritical use of coarse (aggregated) spatial ES data and indicators in strategies for land use planning and forest conservation.

Non-canonical Mechanisms of Presynaptic Kainate Receptors Controlling Glutamate Release.

A metabotropic modus operandi for kainate receptors (KARs) was first discovered in 1998 modulating GABA release. These receptors have been also found to modulate glutamate release at different synapses in several brain regions. Mechanistically, a general biphasic mechanism for modulating glutamate release by presynaptic KARs with metabotropic actions has emerged, with low KA concentrations invoking an increase in glutamate release, whereas higher concentrations of KA mediate a decrease in the release of this neurotransmitter. The molecular mechanisms underpinning the opposite modulation of glutamate release are distinct, with a G-protein-independent, adenylate cyclase (AC)- and protein kinase A (PKA)-dependent mechanism mediating the facilitation of glutamate release, while a G-protein dependent mechanism (with or without protein kinase recruitment) is involved in the decrease of neurotransmitter release. In the present review, we revisit the mechanisms underlying the non-canonical modus operandi of KARs effecting the bimodal control of glutamatergic transmission in different brain regions, and address the possible functions that this modulation may support.

Mutation of the HERC 1 Ubiquitin Ligase Impairs Associative Learning in the Lateral Amygdala.

Tambaleante (tbl/tbl) is a mutant mouse that carries a spontaneous Gly483Glu substitution in the HERC1 (HECT domain and RCC1 domain) E3 ubiquitin ligase protein (HERC1). The tbl/tbl mutant suffers an ataxic syndrome given the almost complete loss of cerebellar Purkinje cells during adult life. More recent analyses have identified alterations at neuromuscular junctions in these mice, as well as in other neurons of the central nervous system, such as motor neurons in the spinal cord, or pyramidal neurons in the hippocampal CA3 region and the neocortex. Accordingly, the effect of the tbl/tbl mutation apparently extends to other regions of the nervous system far from the cerebellum. As HERC1 mutations in humans have been correlated with intellectual impairment, we studied the effect of the tbl/tbl mutation on learning. Using a behavioral test, ex vivo electrophysiological recordings, immunohistochemistry, and Golgi method, we analyzed the associative learning in the lateral amygdala of the tbl/tbl mouse. The tbl/tbl mice perform worse than wild-type animals in the passive avoidance test, and histologically, the tbl/tbl mice have more immature forms of dendritic spines. In addition, LTP cannot be detected in these animals and their STP is dampened, as is their glutamatergic input to the lateral amygdala. Together, these data suggest that HERC1 is probably involved in regulating synaptic function in the amygdala. Indeed, these results indicate that the tbl/tbl mutation is a good model to analyze the effect of alterations to the ubiquitin-proteasome pathway on the synaptic mechanisms involved in learning and its defects.

Conditional self-discrimination enhances dendritic spine number and dendritic length at prefrontal cortex and hippocampal neurons of rats.

We studied conditional self-discrimination (CSD) in rats and compared the neuronal cytoarchitecture of untrained animals and rats that were trained in self-discrimination. For this purpose, we used thirty 10-week-old male rats were randomized into three groups: one control group and two conditioning groups: a comparison group (associative learning) and an experimental group (self-discrimination). At the end of the conditioning process, the experimental group managed to discriminate their own state of thirst. After the conditioning process, dendritic morphological changes in the pyramidal neurons of the prefrontal cortex and CA1 region of the dorsal hippocampus were evaluated using Golgi-Cox stain method and then analyzed by the Sholl method. Differences were found in total dendritic length and spine density. Animals trained in self-discrimination showed an increase in the dendritic length and the number of dendritic spines of neurons of the prefrontal cortex and CA1 region of the dorsal hippocampus. Our data suggest that conditional self-discrimination improves the connectivity of the prefrontal cortex and dorsal CA1, which has implications for memory and learning processes.

Disfunción eréctil en población masculina mayor de 35 años en la ciudad de Siguatepeque / Erectile dysfunction in men above 35 in Siguatepeque, Honduras

Las funciones sexuales y eréctiles son importantes en la salud de los hombres y el bienestar de las parejas. La disfunción eréctil (DE) tiene una alta prevalencia fundamentalmente en las últimas décadas de la vida y se halla relacionada con múltiples factores de riesgo. Objetivo: establecer algunos factores de riesgo y enfermedades concomitantes así como la prevalencia de la disfunción eréctil en la población masculina mayor de 35 años de la ciudad de Siguatepeque, Honduras, agosto del 2009. Metodología; estudio descriptivo de corte transversal. La población fue de 5,200 hombres mayores de 35 años. La muestra de 371 hombres. El método de muestreo fue estratificado según barrios de la ciudad. La unidad de estudio fue seleccionada en forma aleatoria. Para la recolección de datos se utilizaron dos instrumentos, una encuesta con datos de carácter general; otro instrumento utilizado fue el Test de SHIM (Sexual Health Inventory for Men), cuestionario sobre salud sexual masculina, versión abreviada del IIEF (Índice Internacional de Función Eréctil) del que se seleccionaron 5 preguntas sobre sexualidad masculina en los últimos 6 meses, con el propósito de detectar DE en grupos de riesgo. Se considera DE cuando la puntuación es igual o inferior a 21. Resultados; La prevalencia de DE encontrada fue de 214(58%) del total de la muestra, los grados de disfunción fueron: Leve 114(53%), de Leve a Moderada 57(27%), Moderada 18(8%), y Grave 25(12%). La DE encontrada según rangos de edad fue para mayores de 60 años 94(44%), de 45 a 59 años 95(45%), de 35 a 44 años 25(11%). Los hábitos tóxicos: hombres que en el pasado ingirieron bebidas alcohólicas y al momento de la entrevista consumían y tenían DE 104(49%) y 50(23%) respectivamente. Tabaquismo como antecedente de consumo y al momento de la entrevista presentaban DE, 96(45%) y 55(26%) respectivamente. El consumo de otras drogas 3(1%). Las enfermedades concomitantes que se relacionan con DE fueron: problemas cardiovascular...

Kainate receptor-mediated inhibition of glutamate release involves protein kinase A in the mouse hippocampus.

The mechanisms involved in the inhibition of glutamate release mediated by the activation of presynaptic kainate receptors (KARs) at the hippocampal mossy fiber-CA3 synapse are not well understood. We have observed a long-lasting inhibition of CA3 evoked excitatory postsynaptic currents (eEPSCs) after a brief application of kainate (KA) at concentrations ranging from 0.3 to 10 muM. The inhibition outlasted the change in holding current caused by the activation of ionotropic KARs in CA3 pyramidal cells, indicating that this action is not contingent on the opening of the receptor channels. The inhibition of the eEPSCs by KA was prevented by G protein and protein kinase A (PKA) inhibitors and was enhanced after stimulation of the adenylyl cyclase (AC) with forskolin. We conclude that KARs present at mossy fiber terminals mediate the inhibition of glutamate release through a metabotropic mechanism that involves the activation of an AC-second messenger cAMP-PKA signaling cascade.