Reactive oxygen species, Ca2+ signaling and mitochondrial NAD(P)H level in adrenal glomerulosa cells

The acute effects of ultraviolet light, the superoxide-generating xanthine-xanthine oxidase system and H(2)O(2) to on calcium signaling and mitochondrial pyridine nucleotide metabolism were investigated in rat glomerulosa cells. UV light induced the formation of superoxide, that, similar to exogenously applied superoxide and H(2)O(2), decreased the level of mitochondrial NAD(P)H. Free radical scavengers antagonized this effect of UV light. Extracellularly generated superoxide elicited Ca(2+) transients and inhibited angiotensin II-induced cytoplasmic Ca(2+) signaling. Low intensity UV light did not affect basal [Ca(2+)] and failed to influence Ca(2+) signaling induced by depolarization or store depletion. UV light of the same low power reduced both cytoplasmic and mitochondrial Ca(2+) signals induced by angiotensin II. The lack of UV effect on inositol phosphate formation indicates that the inhibition of cytoplasmic Ca(2+) signaling is due to reduced Ca(2+) release from InsP(3)-sensitive stores. Decreased mitochondrial Ca(2+) uptake may be attributed to UV-induced perturbation of the perimitochondrial microdomain.     

4,5-Disubstituted cis-pyrrolidinones as inhibitors of type II 17beta-hydroxysteroid dehydrogenase. Part 3. Identification of lead candidate

A series of 4,5-disubstituted cis-pyrrolidinones was investigated as inhibitors of 17beta-HSD II for the treatment of osteoporosis. Biochemical data for several compounds are given. Compound 42 was selected as the lead candidate.     

The Autism Psychodynamic Evaluation of Changes (APEC) scale: A reliability and validity study on a newly developed standardized psychodynamic assessment for youth with Pervasive Developmental Disorders

The present study was designed to examine the reliability and validity of the Autism Psychodynamic Evaluation of Changes (APEC) scale, developed to assess the evolution in individuals with autism under treatment. The APEC scale focuses on the key role of impairment in body image construction, which requires cross-modal sensory integration through emotional communication with motor representations. Thus, the body image construction is associated simultaneously with spatial and temporal organization and allows the emergence of self- and others-representations. The use of the APEC scale, with its seven domains (expression of emotion in relationships, eye contact, body image, graphic productions, exploration of space and objects, time perception, and verbal language), underlines the importance in autistic disorder of anxieties related to body and spatial representations, and of impairment in the body ego construction which is closely linked to the emergence of individuation/separation processes. This study was conducted on 73 children and adolescents with autistic disorder. They were recruited in day care facilities where two caregivers independently gave their ratings based on their clinical observation on a daily basis during the same month. Analyses included assessing construct validity through correspondence analyses and inter-rater reliability using kappa coefficients. The APEC scale offers a reliable and validated psychodynamic assessment of interest for professionals (such as child psychiatrists, caregivers, therapists or teachers) and researchers working with children, adolescents and adults with autistic disorder, especially in the follow-up of their evolution. The APEC scale provides an approach at the interface of psychoanalysis and neuroscience, and is also of interest for clinical and developmental psychology. Using the APEC scale in a range of different practical and research settings will foster links between psychoanalytic perspectives and educational training for children with autistic disorder, and will contribute to the dialogue between psychoanalysis, neuroscience and psychology.     

Is subarctic forest advance able to keep pace with climate change?

Recent climate warming and scenarios for further warming have led to expectations of rapid movement of ecological boundaries. Here we focus on the circumarctic forest–tundra ecotone (FTE), which represents an important bioclimatic zone with feedbacks from forest advance and corresponding tundra disappearance (up to 50% loss predicted this century) driving widespread ecological and climatic changes. We address FTE advance and climate history relations over the 20th century, using FTE response data from 151 sites across the circumarctic area and site‐specific climate data. Specifically, we investigate spatial uniformity of FTE advance, statistical associations with 20th century climate trends, and whether advance rates match climate change velocities (CCVs). Study sites diverged into four regions (Eastern Canada; Central and Western Canada and Alaska; Siberia; and Western Eurasia) based on their climate history, although all were characterized by similar qualitative patterns of behaviour (with about half of the sites showing advancing behaviour). The main associations between climate trend variables and behaviour indicate the importance of precipitation rather than temperature for both qualitative and quantitative behaviours, and the importance of non‐growing season as well as growing season months. Poleward latitudinal advance rates differed significantly among regions, being smallest in Eastern Canada (~10 m/year) and largest in Western Eurasia (~100 m/year). These rates were 1–2 orders of magnitude smaller than expected if vegetation distribution remained in equilibrium with climate. The many biotic and abiotic factors influencing FTE behaviour make poleward advance rates matching predicted 21st century CCVs (~10³–10⁴ m/year) unlikely. The lack of empirical evidence for swift forest relocation and the discrepancy between CCV and FTE response contradict equilibrium model‐based assumptions and warrant caution when assessing global‐change‐related biotic and abiotic implications, including land–atmosphere feedbacks and carbon sequestration.     

Tipping Points in the Mangrove March: Characterization of Biogeochemical Cycling Along the Mangrove–Salt Marsh Ecotone

Ecosystems - Coastal wetland vegetation communities can respond to sea level rise via the encroachment of more salt- and inundation-tolerant species into existing vegetation communities. Black...     

siSPOTR: a tool for designing highly specific and potent siRNAs for human and mouse

RNA interference (RNAi) serves as a powerful and widely used gene silencing tool for basic biological research and is being developed as a therapeutic avenue to suppress disease-causing genes. However, the specificity and safety of RNAi strategies remains under scrutiny because small inhibitory RNAs (siRNAs) induce off-target silencing. Currently, the tools available for designing siRNAs are biased toward efficacy as opposed to specificity. Prior work from our laboratory and others’ supports the potential to design highly specific siRNAs by limiting the promiscuity of their seed sequences (positions 2–8 of the small RNA), the primary determinant of off-targeting. Here, a bioinformatic approach to predict off-targeting potentials was established using publically available siRNA data from more than 50 microarray experiments. With this, we developed a specificity-focused siRNA design algorithm and accompanying online tool which, upon validation, identifies candidate sequences with minimal off-targeting potentials and potent silencing capacities. This tool offers researchers unique functionality and output compared with currently available siRNA design programs. Furthermore, this approach can greatly improve genome-wide RNAi libraries and, most notably, provides the only broadly applicable means to limit off-targeting from RNAi expression vectors.     

Comparing survey methods for monitoring vegetation change through time in a restored peatland

Monitoring is an essential step to assess vegetation trajectories post-restoration and ultimately evaluate success. In this paper, we compare two monitoring methods, the line-point intercept (LPI) and the permanent plot (PP) methods, for evaluating plant recovery of a restored cut-over peatland (8.5 ha), following a “moss layer transfer technique”. We used the LPI method to estimate covers (from frequency measures) for each plant species using a systematic grid of approximately 5,700 points (every 3 m × 5 m). In parallel, 43 PP (3 m × 8 m) were established and used to evaluate plant covers. The post-restoration recovery of vegetation was assessed against a reference ecosystem encompassing the variation in species cover from natural undisturbed peatlands in the same region. For all plant groups considered, the LPI consistently showed higher cover estimates than the PP method. Discrepancy between the two methods was particularly evident for the Ericaceae group. A complementary sampling method, the line-intercept (LI), showed strong correlations with the visual estimations of Ericaceae covers (akin to PP), suggesting an overestimation from the LPI method. Most life form groups of the restored peatlands are developing a structure similar to the regional reference ecosystem 8 years post-restoration with the herb group being still most dissimilar. Indeed, when analyzing the temporal evolution of the different key peatland plant components, several are within the range of regional abundance values or moving positively towards range of cover abundance of the reference system such as Sphagnum cover, a key peat-accumulating plant group.