Observations on the biology of Leuciscus ‘svallize’ in the Kremasta reservoir (Greece)

The age, growth, feeding habits and reproductive biology of Leuciscus svallize in artificial lake Kremasta (Greece), are described. There is a considerable similarity in the feeding and reproductive characteristics between L. svallize and L. cephalus and also a similarity in the life span, growth patterns and age of maturation between L. svallize and some southern L. cephalus populations, which may suggest similar responses of closely related taxa to similar conditions.     

Preparation of the N-(4'-hydroxy-[3'-125I]iodophenethyl)-6-(4-O-diethylstilbestryl)hexanam ide for diethylstilbestrol radioimmunoassays.

The synthesis of a radioiodinated diethylstilbestrol (DES) derivative is described. This derivative was prepared by coupling the previously synthesized active ester of 6-(4-O-diethylstilbestryl)hexanoic acid with mono-[125I]iodotyramine in dry tetrahydrofuran (20 to 22 C, 16 hours). The mono-[125I]iodotyramine was prepared using a chloramine-T method and purified by paper electrophoresis. The final product, N-(4'-hydroxy-[3'-125I]iodophenethyl)-6-(4-O- diethylstilbestryl)hexanamide, was separated by thin-layer chromatography (cyclohexane/ethanol/NH4OH 2.5 N/acetone; 40:50:5:20, v/v/v/v); it was stable for 2 months in ethanol at 4 C and had a specific activity higher than 540 Ci/mmol. The [125I]DES amide synthesized was found to retain the immunoreactivity of DES, since it competed with [3H]DES or DES in an in vitro radioimmunoassay system for the binding sites of a rabbit anti-DES antibody; thus, it seems to be capable of replacing the tritiated tracer used so far in DES radioimmunoassays.     

Use of short sequence repeat DNA polymorphisms after PCR amplification to detect the parental origin of the additional chromosome 21 in Down syndrome.

The origin of nondisjunction in trisomy 21 has so far been studied using cytogenetic heteromorphisms and DNA polymorphisms using Southern blot analysis. Short sequence repeats have recently been described as an abundant class of DNA polymorphisms in the human genome, which can be typed using the polymerase chain reaction (PCR) amplification. We describe the usage of such markers on chromosome 21 in the study of parental origin of the additional chromosome 21 in 87 cases of Down syndrome. The polymorphisms studied were (a) two (GT)n repeats and a poly(A) tract of an Alu sequence within the HMG14 gene and (b) a (GT)n repeat of locus D21S156. The parental origin was determined in 68 cases by studying the segregation of polymorphic alleles in the nuclear families (either by scoring three different alleles in the proband or by dosage comparison of two different alleles in the proband). Our results demonstrate the usefulness of highly informative PCR markers for the study of nondisjunction in Down syndrome.     

The Preprotein Binding Domain of SecA Displays Intrinsic Rotational Dynamics

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Spatial co‐localisation of extreme weather events: a clear and present danger

Extreme weather events have become a dominant feature of the narrative surrounding changes in global climate with large impacts on ecosystem stability, functioning and resilience; however, understanding of their risk of co‐occurrence at the regional scale is lacking. Based on the UK Met Office’s long‐term temperature and rainfall records, we present the first evidence demonstrating significant increases in the magnitude, direction of change and spatial co‐localisation of extreme weather events since 1961. Combining this new understanding with land‐use data sets allowed us to assess the likely consequences on future agricultural production and conservation priority areas. All land‐uses are impacted by the increasing risk of at least one extreme event and conservation areas were identified as the hotspots of risk for the co‐occurrence of multiple event types. Our findings provide a basis to regionally guide land‐use optimisation, land management practices and regulatory actions preserving ecosystem services against multiple climate threats.     

Diversity of dimethylsulfide-degrading methanogens and sulfate-reducing bacteria in anoxic sediments along the Medway Estuary,UK

Methane is a powerful greenhouse gas but the microbial diversity mediating methylotrophic methanogenesis is not well-characterized. One overlooked route to methane is via the degradation of dimethylsulfide (DMS), an abundant organosulfur compound in the environment. Methanogens and sulfate-reducing bacteria (SRB) can degrade DMS in anoxic sediments depending on sulfate availability. However, we know little about the underlying microbial community and how sulfate availability affects DMS degradation in anoxic sediments. We studied DMS-dependent methane production along the salinity gradient of the Medway Estuary (UK) and characterized, for the first time, the DMS-degrading methanogens and SRB using cultivation-independent tools. DMS metabolism resulted in high methane yield (39%–42% of the theoretical methane yield) in anoxic sediments regardless of their sulfate content. Methanomethylovorans, Methanolobus and Methanococcoides were dominant methanogens in freshwater, brackish and marine incubations respectively, suggesting niche-partitioning of the methanogens likely driven by DMS amendment and sulfate concentrations. Adding DMS also led to significant changes in SRB composition and abundance in the sediments. Increases in the abundance of Sulfurimonas and SRB suggest cryptic sulfur cycling coupled to DMS degradation. Our study highlights a potentially important pathway to methane production in sediments with contrasting sulfate content and sheds light on the diversity of DMS degraders.     

Substrate-Activated Conformational Switch on Chaperones Encodes a Targeting Signal in Type III Secretion

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Highlights? The targeting signal of TTS substrates to the ATPase was identified ? The ATPase engages the chaperone-substrate complex but not the free chaperone ? The ATPase recognizes a conformational change induced by the substrate to the chaperone ? Abrogation of the ternary complex results in secretion and infection defects     

Suicidal ideation and reported suicide attempts in Greece during the economic crisis

The financial crisis in Greece is largely impinging on the health and mental health of the population, raising concerns about a potential rise in suicide rates. The aim of this study was to explore changes in suicidal ideation and reported suicide attempts between 2009 and 2011 in a representative sample of the population and in several population subgroups. The socio‐economic predictors of suicidal ideation and suicide attempts in 2011 were also investigated. Two nationwide cross‐sectional telephone surveys were conducted in 2009 and 2011 using the same methodology. A random and representative sample of 2192 and 2256 people, respectively, took part in the surveys. Between 2009 and 2011, there was a substantial increase in the prevalence of suicidal ideation and reported suicide attempts. People suffering from depression, men, married individuals, people experiencing financial strain, people with low interpersonal trust, and individuals with a history of suicide attempts were particularly vulnerable.