DNA isolation of mucus from Salmo trutta (Linnaeus, 1758) and Thymallus thymallus (Linnaeus, 1758) as an alternative method to conventional fin‐clipping

The first objective of the actual project was to investigate if mucus from Salmo trutta (Linnaeus, 1758) and Thymallus thymallus (Linnaeus, 1758) is suitable for DNA extraction. In the second step, it was analyzed if the avoidance of environmentally hazardous chemicals could lead to sufficiently pure DNA isolation. Finally, it was examined if samples taken from different fish body parts yielded different grades of purity of the extracted DNA. Mucus was collected from 552 individuals of S. truttaand T. thymallusfrom 2012 to 2015. DNA was extracted with two different kits (E.Z.N.A.^® Insect DNA Kit and my‐Budget DNA Mini Kit) and two different swabs (my‐Budget roughened laminated sterile cotton swabs and common autoclaved cotton swabs). The results showed that the my‐Budget DNA Mini Kit in combination with the my‐Budget roughened laminated sterile cotton swabs was the most suitable method. It is a non‐destructive and swift technique that results in the concentration of DNA being high and pure.     

Molecular characterization of Vulmar1, a complete mariner transposon of sugar beet and diversity of mariner- and En/Spm-like sequences in the genus Beta.

Transposons of the Tc1-mariner superfamily are widespread in eukaryotic genomes. We have isolated the mariner element Vulmar1 from Beta vulgaris L., which is 3909 bp long and bordered by perfect terminal inverted repeats of 32 bp with homology to terminal inverted repeats of transposons from soybean and rice. According to a characteristic amino acid signature, Vulmar1 can be assigned to the DD39D group of mariner transposons. Vulmar1 is flanked by a 5'-TA-3' target site duplication that is typical for mariner transposons. Southern hybridization revealed that mariner-like copies are highly abundant in Beta species, and sequence analysis of 10 transposase fragments from representative species of the four Beta sections revealed an identity between 34% and 100% after conceptual translation. By fluorescent in situ hybridization, Vulmar1 was detected in distal euchromatin as well as in some intercalary and pericentromeric regions of all B. vulgaris chromosomes. In addition, using PCR, we were able to amplify fragments of the transposase gene of En/Spm-like transposons in the genus Beta. En/Spm-like transposase sequences are highly amplified in four Beta sections and showed a considerable degree of conservation (88.5-100%) at the protein level, while the homology to corresponding regions of En/Spm transposons of other plant species ranges from 49.5% to 62.5%. By fluorescent in situ hybridization, En/Spm-like transposon signals of strong intensity were detected on all chromosomes of B. vulgaris.     

Global change effects on a mechanistic decomposer food web model

Global change may affect the structure and functioning of decomposer food webs through qualitative changes in freshly fallen litter. We analyzed the predicted effects of a changing environment on a dynamic model of a donor‐controlled natural decomposer ecosystem near Wekerom, the Netherlands. This system consists of fungi, bacteria, fungivores, bacterivores and omnivores feeding on microbiota and litter as well. The model concentrates on carbon and nitrogen flows through the trophic niches that define this decomposer system, and is designed to predict litter masses and abundances of soil biota. For modeling purposes, the quality of freshly fallen leaf litter is defined in terms of nitrogenous and non‐nitrogenous components, of which refractory and labile forms are present. The environmental impacts of elevated CO₂, enhanced UV‐B and eutrophication, each with their own influence on leaf litter quality, are studied. The model predicts steady‐state dynamics exclusively, for all three scenarios. Environmental changes impact most demonstratively on the highest trophic niches, and affect microbiotic abundances and litter decomposition rates to a lesser extent. We conclude that the absence of trophic cascade effects may be attributed to weak trophic links, and that non‐equilibrium dynamics occurring in the system are generally because of encounter rates based on fractional substrate densities in the litter. We set out a number of experimentally testable hypotheses that may improve understanding of ecosystem dynamics.     

Hydroxyproline O‐arabinosyltransferase mutants oppositely alter tip growth in Arabidopsis thaliana and Physcomitrella patens

Hydroxyproline O‐arabinosyltransferases (HPATs) are members of a small, deeply conserved family of plant‐specific glycosyltransferases that add arabinose sugars to diverse proteins including cell wall‐associated extensins and small signaling peptides. Recent genetic studies in flowering plants suggest that different HPAT homologs have been co‐opted to function in diverse species‐specific developmental contexts. However, nothing is known about the roles of HPATs in basal plants. We show that complete loss of HPAT function in Arabidopsis thaliana and the moss Physcomitrella patens results in a shared defect in gametophytic tip cell growth. Arabidopsis hpat1/2/3 triple knockout mutants suffer from a strong male sterility defect as a consequence of pollen tubes that fail to fully elongate following pollination. Knocking out the two HPAT genes of Physcomitrella results in larger multicellular filamentous networks due to increased elongation of protonemal tip cells. Physcomitrella hpat mutants lack cell‐wall associated hydroxyproline arabinosides and can be rescued with exogenous cellulose, while global expression profiling shows that cell wall‐associated genes are severely misexpressed, implicating a defect in cell wall formation during tip growth. Our findings point to a major role for HPATs in influencing cell elongation during tip growth in plants.     

Emotional and Affective Temperaments in Smoking Candidates for Bariatric Surgery

Introduction

The prevalence of smoking habits in severe obesity is higher than in the general population. There is some evidence that smokers have different temperaments compared to non-smokers. The aim of this study is to evaluate the associations between smoking status (smokers, ex-smokers and non-smokers) and temperament characteristics in bariatric surgery candidates.

Methods

We analyzed data on temperament of 420 bariatric surgery candidates, as assessed by the AFECTS scale, in an exploratory cross-sectional survey of bariatric surgery candidates who have been grouped into smokers, ex-smokers and non-smokers.

Results

We detected significant statistical differences in temperament related to the smoking status in this population after controlling the current use of psychiatric medication. Smokers had higher anxiety and lower control than non-smokers. Ex-smokers with BMI >50 kg/m² presented higher coping and control characteristics than smokers.

Conclusions

Smoking in bariatric surgery candidates was associated with lower control and higher anxious temperament, when controlled by current use of psychiatric medication. Smokers with BMI >50 kg/m² presented lower coping and control than ex-smokers. Assessment of temperament in bariatric surgery candidates may help in decisions about smoking cessation treatment and prevention of smoking relapse after surgery.     

Adenylyl Cyclase Activity in Postmortem Human Brain: Evidence of Altered G Protein Mediation in Alzheimer''s Disease

The effects of agonal status, postmortem delay, and age on human brain adenylyl cyclase activity were determined in membrane preparations of frontal cortex from a series of 18 nondemented subjects who had died with no history of neurological or psychiatric disease. Basal and guanosine 5'-O-(3-thiotriphosphate)-, aluminum fluoride-, and forskolin-stimulated enzyme activities were not significantly reduced over an interval from death to postmortem of between 3 and 37 h and were also not significantly different between individuals dying with a long terminal phase of an illness and those dying suddenly. Basal and aluminum fluoride-stimulated enzyme activities showed a negative correlation with increasing age of the individual. In subsequent experiments, basal and guanosine 5'-O-(3-thiotriphosphate)-, aluminum fluoride-, and forskolin-stimulated enzyme activities were compared in five brain regions from a series of eight Alzheimer's disease and seven matched nondemented control subjects. No significant differences were observed between the groups for either basal activity or activities in response to forskolin stimulation of the catalytic subunit of the enzyme. In contrast, enzyme activities in response to stimulation with guanosine 5'-O-(3-thiotriphosphate) and aluminum fluoride were significantly reduced in preparations of neocortex and cerebellum from the Alzheimer's disease cases compared with the nondemented controls. Lower guanosine 5'-O-(3-thiotriphosphate)-, but not aluminum fluoride-, stimulated activity was also observed in preparations of frontal cortex from a group of four disease controls compared with nondemented control values. The disease control group, which contained Parkinson's disease and progressive supranuclear palsy patients, showed increased forskolin-stimulated activity compared with both the nondemented control and the Alzheimer's disease groups. These findings indicate a widespread impairment of G protein-stimulated adenylyl cyclase activity in Alzheimer's disease brain, which occurs in the absence of altered enzyme catalytic activity and which is unlikely to be the result of non-disease-related factors associated with the nature of terminal illness of individuals.     

Altered beta-secretase enzyme kinetics and levels of both BACE1 and BACE2 in the Alzheimer's disease brain

beta-Secretase is the rate limiting enzymatic activity in the production of amyloid-beta peptide, the primary component of senile plaque pathology in Alzheimer's disease (AD). This study performed the first comparative analysis of beta-secretase enzyme kinetics in AD and control brain tissue. Results found V(max) values for beta-secretase to be significantly increased, and K(m) values unchanged in AD temporal cortex compared to matched control temporal cortex. The increased V(max) in AD cases, did not correlate with levels of BACE1, and decreased BACE1 and BACE2 levels correlated with the severity of neurofibrillary pathology (I-VI), and synaptic loss in AD. These results indicate that increased V(max) for beta-secretase is a feature of AD pathogenesis and this increase does not correlate directly with levels of BACE1, the principal beta-secretase in brain.