39 research outputs found
Anthrax outbreak in a Swedish beef cattle herd - 1st case in 27 years: Case report
After 27 years with no detected cases, an outbreak of anthrax occurred in a beef cattle herd in the south of Sweden. The outbreak was unusual as it occurred in winter, in animals not exposed to meat-and-bone meal, in a non-endemic country
Phylogenetic relatedness determined between antibiotic resistance and 16S rRNA genes in actinobacteria
Selection for increased nitrogen fixation in red clover
Plants were selected and bred from the modal yield class of the population and from the class showing the largest yield (and nitrogen content), under conditions of test-tube culture using a single strain of rhizobia as inoculum. Progeny tests made on about 60 crosses within each group over two generations showed larger yields in families raised from the most effective parent plants, but the average effect of selection was small (about 5% dry weight increase). When the same material was tested with other strains of bacteria the effect of selection was less, but did not entirely disappear. In these conditions, selection was partly for increased symbiotic nitrogen fixation and partly for tolerance of the restricted conditions of growth.
RESP-653
Adenophora liliifolia: condition of its populations in Central Europe
This study deals with populations of the European-South-Siberian geoelement Adenophora liliifolia (L.) A. DC. in
the Czech Republic, Slovakia, Hungary, Romania, and Poland, where this species has its European periphery distribution.
We studied the population size, genetic variability, site conditions, and vegetation units in which A. liliifolia
grows. Recent and historical localities of A. liliifolia were ranked into six vegetation units of both forest and non-forest
character. A phytosociological survey showed differences in the species composition among localities. Only a weak
pattern of population structure was observed (only 22% of total genetic variation present at the interpopulation level,
AMOVA analysis), with moderate values for gene diversity (Hj = 0.141) and polymorphism (P = 27.6%). Neighborjoining
and Bayesian clusterings suggest a similar genetic background for most of the populations from Slovakia, the
Czech Republic, and Poland, contrary to the populations from Hungary, Romania, as well as two populations from
Central and South Slovakia. This might be explained by a relatively recent fragmentation of the A. liliifolia populations
in Central Europe. Nevertheless, it seems that several populations in Romania, South Hungary, and Slovakia
were isolated for a longer period of time and their genetic differentiation is more evident
Bacterial diversity and abundance of a creek valley sites reflected soil pH and season
The effect of environmental factors on bacterial
and actinobacterial communities was assessed to predict
microbial community structure in natural gradients.
Bacterial and actinobacterial communities were studied
at four sites differing in vegetation and water regime:
creek sediment, wet meadow, dry meadow and deciduous
forest located in a shallow valley. The vegetation structure
was assessed by phytocoenological releves. T-RFLP and
quantitative PCR were used to determine community
composition and abundances. Significant relationships
between bacterial community structure and selected
soil traits at sites located relatively close to each other
(within 200 m) were demonstrated. Both the quantity
and structure of bacterial communities were significantly
influenced by organic matter content, soil moisture and
pH. Bacterial diversity was higher in summer, while that
of actinobacteria increased in winter. The Simpsonâs
evenness E was significantly correlated with soil organic
matter content. Soil pH had the greatest influence on
bacterial community structure showing higher within-site
variability in summer than in winter
Atomic resolution crystal structure of Sapp2p, a secreted aspartic protease from Candida parapsilosis
The virulence of theCandidapathogens is enhanced by the production of secreted aspartic proteases, which therefore represent possible targets for drug design. Here, the crystal structure of the secreted aspartic protease Sapp2p fromCandida parapsilosiswas determined. Sapp2p was isolated from its natural source and crystallized in complex with pepstatin A, a classical aspartic protease inhibitor. The atomic resolution of 0.83â
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allowed the protonation states of the active-site residues to be inferred. A detailed comparison of the structure of Sapp2p with the structure of Sapp1p, the most abundantC. parapsilosissecreted aspartic protease, was performed. The analysis, which included advanced quantum-chemical interaction-energy calculations, uncovered molecular details that allowed the experimentally observed equipotent inhibition of both isoenzymes by pepstatin A to be rationalized.</jats:p
Impact of sex and depressed mood on the central regulation of cardiac autonomic function
Cardiac autonomic dysregulation has been implicated in the comorbidity of major psychiatric disorders and cardiovascular disease, potentially through dysregulation of physiological responses to negative stressful stimuli (here, shortened to stress response). Further, sex differences in these comorbidities are substantial. Here, we tested the hypothesis that mood- and sex-dependent alterations in brain circuitry implicated in the regulation of the stress response are associated with reduced peripheral parasympathetic activity during negative emotional arousal. Fifty subjects (28 females) including healthy controls and individuals with major depression, bipolar psychosis and schizophrenia were evaluated. Functional magnetic resonance imaging and physiology (cardiac pulse) data were acquired during a mild visual stress reactivity challenge. Associations between changes in activity and functional connectivity of the stress response circuitry and variations in cardiovagal activity [normalized high frequency power of heart rate variability (HFn)] were evaluated using GLM analyses, including interactions with depressed mood and sex across disorders. Our results revealed that in women with high depressed mood, lower cardiovagal activity in response to negative affective stimuli was associated with greater activation of hypothalamus and right amygdala and reduced connectivity between hypothalamus and right orbitofrontal cortex, amygdala, and hippocampus. No significant associations were observed in women with low levels of depressed mood or men. Our results revealed mood- and sex-dependent interactions in the central regulation of cardiac autonomic activity in response to negative affective stimuli. These findings provide a potential pathophysiological mechanism for previously observed sex differences in the comorbidity of major depression and cardiovascular disease
Pathogen quantitation in complex matrices : a multi-operator comparison of DNA extraction methods with a novel assessment of PCR inhibition
Background: Mycobacterium bovis is the aetiological agent of bovine tuberculosis (bTB), an important recrudescent zoonosis, significantly increasing in British herds in recent years. Wildlife reservoirs have been identified for this disease but the mode of transmission to cattle remains unclear. There is evidence that viable M. bovis cells can survive in soil and faeces for over a year.
Methodology/Principal Findings: We report a multi-operator blinded trial for a
rigorous comparison of five DNA extraction methods from a variety of soil and
faecal samples to assess recovery of M. bovis via real-time PCR detection. The
methods included four commercial kits: the QIAamp Stool Mini kit with a pretreatment
step, the FastDNAÂź Spin kit, the UltraCleanTM and PowerSoilTM soil kits
and a published manual method based on phenol:chloroform purification, termed
Griffiths. M. bovis BCG Pasteur spiked samples were extracted by four operators and
evaluated using a specific real-time PCR assay. A novel inhibition control assay was
used alongside spectrophotometric ratios to monitor the level of inhibitory
compounds affecting PCR, DNA yield, and purity. There were statistically
significant differences in M. bovis detection between methods of extraction and types
of environmental samples; no significant differences were observed between
operators. Processing times and costs were also evaluated. To improve M. bovis
detection further, the two best performing methods, FastDNAÂź Spin kit and
Griffiths, were optimised and the ABI TaqMan environmental PCR Master mix was
adopted, leading to improved sensitivities.
Conclusions: M. bovis was successfully detected in all environmental samples; DNA
extraction using FastDNAÂź Spin kit was the most sensitive method with highest
recoveries from all soil types tested. For troublesome faecal samples, we have used
and recommend an improved assay based on a reduced volume, resulting in detection limits of 4.25 x 105 cells g-1 using Griffiths and 4.25 x 106 cells g-1 using
FastDNAÂź Spin kit