bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of temperature and duration of ensiling on in vitro degradation of maize silages in rumen fluid
Authors: Ali M. , Cone J. W. , Khan N. A. , Hendriks W. H. , Struik P. C. 
Published: September 2014

SummaryThe effects of ensiling temperature and duration of ensiling on the feeding quality of whole‐crop maize (Zea mays L.) silages were investigated. Samples of one cultivar of maize plants were collected from two different fields, grown in different years on sandy soils. Samples were collected when the whole‐plant dry matter content was approximately 330 g/kg. Maize plants were chopped and ensiled in mini silos at three different ambient temperatures (5, 12 and 18 °C). The ensiling temperature affected the ensiling fermentation processes, causing different rates of pH decline and different final pH values. Samples from the silos were taken after 0 (not ensiled, i.e. control), 4, 8 and 16 weeks of ensiling. The silage samples were not dried, but ground‐frozen under liquid nitrogen to pass a 1‐mm sieve. The gas production technique was used to evaluate the influence of the ensiling temperature and the duration of ensiling on the degradation of the silage samples in rumen fluid. The gas production was highest when the maize was ensiled at 12 °C (p < 0.0001). An increase in ensiling duration caused a decrease in silage pH, accompanied by a decrease in gas production (p < 0.0001). The decrease in gas production was linearly related to the decrease in pH at the three temperatures. The present study shows that both ensiling temperature and ensiling duration play a significant role in the rumen degradability of maize silage.
Literacy, poverty and schooling: what matters in young people's education?
Authors: Comber Barbara 
Published: September 2014

AbstractThis paper draws upon several decades of literacy research in schools in high‐poverty environments to explore what matters in young people's education. In dialogue with themes from Kevin Marjoribanks' work, such as student aspirations, family environments and teacher expectations, key insights are summarised. Referring to longitudinal case studies and a current ethnographic project, the interplay between literacy, poverty and schooling, and young people's aspirations and education outcomes is explored. Although the work of educators in high‐poverty communities continues to be highly demanding, there are some schools and teachers making a durable positive difference to learner dispositions and literate repertoires. Teacher expectations and discursive practices are crucial in this process.
Influence of bacteria on cell size development and morphology of cultivated diatoms
Authors: Windler Miriam , Bova Dariia , Kryvenda Anastasiia , Straile Dietmar , Gruber Ansgar , Kroth Peter G. 
Published: September 2014

SummaryVegetative cell division in diatoms often results in a decreased cell size of one of the daughter cells, which during long‐term cultivation may lead to a gradual decrease of the mean cell size of the culture. To restore the initial cell size, sexual reproduction is required, however, in many diatom cultures sexual reproduction does not occur. Such diatom cultures may lose their viability once the average size of the cells falls below a critical size. Cell size reduction therefore seriously restrains the long‐term stability of many diatom cultures. In order to study the bacterial influence on the size diminution process, we observed cell morphology and size distribution of the diatoms Achnanthidium minutissimum, Cymbella affiniformis and Nitzschia palea for more than two years in bacteria‐free conditions (axenic cultures) and in cultures that contain bacteria (xenic cultures). We found considerable morphological aberrations of frustule microstructures in A. minutissimum and C. affiniformis when cultivated under axenic conditions compared to the xenic cultures. These variations comprise significant cell length reduction, simplification and rounding of the frustule contour and deformation of the siliceous cell walls, features that are normally found in older cultures shortly before they die off. In contrast, the xenic cultures were well preserved and showed less cell length diminution. Our results show that bacteria may have a fundamental influence on the stability of long‐term cultures of diatoms.
The Joint Impact of Innovation and Knowledge Spillovers on Productivity and Growth for Exporting Firms
Authors: Lööf Hans , Nabavi Pardis 
Published: September 2014

AbstractThis paper provides new insights regarding the role of innovation and localisation on the levels and growth of total factor productivity among exporting firms. For that purpose, we establish a dynamic model using data collected from nearly 10,000 Swedish exporting firms over a 12‐year period. Different innovation proxies are used, and we distinguish between persistent and non‐persistent innovators, while knowledge from outside the firm is measured by a newly developed methodology with detailed spatial resolution. The econometric evidence shows two distinct results. First, persistent innovators benefit significantly more than other exporters from access to a rich spectrum of nearby knowledge. Second, the level of productivity among non‐innovative exporters and exporters that are only temporary engaged in innovation is positively affected by externalities in the most knowledge‐intense local milieus.
Bradykinin enhances invasion of malignant glioma into the brain parenchyma by inducing cells to undergo amoeboid migration
Authors: Seifert Stefanie , Sontheimer Harald 
Published: September 2014

Key pointsGlioma multiforme is a fast expanding and aggressive type of brain tumour that invades healthy brain tissue by migration of single glioma cells along blood vessels.We show that bradykinin, a neuropeptide of the vasculature, induces the formation of small bleb‐like protrusions at the plasma membrane of glioma cellsin vitro, which are regulated by intracellular Ca2+, resulting in contraction of the cytoskeleton, cytoplasmatic flow and activation of Ca2+‐dependent K+and Cl−channels.From ourin vitroexperiments we conclude that bradykinin facilitates glioma invasion by stimulating an amoeboid phenotype of migration.In situexperiments confirmed that bradykinin increases the speed of glioma cell migration, which we have been able to block with blebbistatin, an inhibitor of membrane blebbing, and with the B2 receptor agonist Hoe‐140.The study reveals novel mechanisms of bradykinin‐induced glioma migration and suggests pharmacological targets to reduce glioma invasion.AbstractThe molecular and cellular mechanisms governing cell motility and directed migration in response to the neuropeptide bradykinin are largely unknown. Here, we demonstrate that human glioma cells whose migration is guided by bradykinin generate bleb‐like protrusions. We found that activation of the B2 receptor leads to a rise in free Ca2+from internal stores that activates actomyosin contraction and subsequent cytoplasmic flow into protrusions forming membrane blebs. Furthermore Ca2+activates Ca2+‐dependent K+and Cl−channels, which participate in bleb regulation. Treatment of gliomas with bradykininin situincreased glioma growth by increasing the speed of cell migration at the periphery of the tumour mass. To test if bleb formation is related to bradykinin‐promoted glioma invasion we blocked glioma migration with blebbistatin, a blocker of myosin kinase II, which is necessary for proper bleb retraction. Our findings suggest a pivotal role of bradykinin during glioma invasion by stimulating amoeboid migration of glioma cells.
Nitric oxide synthase deficiency and the pathophysiology of muscular dystrophy
Authors: Tidball James G. , Wehling‐Henricks Michelle 
Published: September 2014

AbstractThe secondary loss of neuronal nitric oxide synthase (nNOS) that occurs in dystrophic muscle is the basis of numerous, complex and interacting features of the dystrophic pathology that affect not only muscle itself, but also influence the interaction of muscle with other tissues. Many mechanisms through which nNOS deficiency contributes to misregulation of muscle development, blood flow, fatigue, inflammation and fibrosis in dystrophic muscle have been identified, suggesting that normalization in NO production could greatly attenuate diverse aspects of the pathology of muscular dystrophy through multiple regulatory pathways. However, the relative importance of the loss of nNOS from the sarcolemma versus the importance of loss of total nNOS from dystrophic muscle remains unknown. Although most current evidence indicates that nNOS localization at the sarcolemma is not required to achieve NO‐mediated reductions of pathology in muscular dystrophy, the question remains open concerning whether membrane localization would provide a more efficient rescue from features of the dystrophic phenotype.
Modulation of the input–output function by GABAA receptor‐mediated currents in rat oculomotor nucleus motoneurons
Authors: Torres‐Torrelo Julio , Torres Blas , Carrascal Livia 
Published: September 2014

Key points
This study deals with synaptic mechanisms involved in the modulation of recruitment threshold and firing rate in ocular motoneurons. In particular, how high and low ambient GABA concentrations modulate these parameters.
In a low ambient GABA concentration, ocular motoneurons exhibit a tonic GABAA receptor‐mediated current that modulates input resistance and recruitment threshold. The modulation effect increased with motoneuron size. Tonic inhibition shifts the firing frequency–current relationship without change in gain.
Independent of cell size, a high ambient GABA concentration reduced input resistance and increased motoneuron recruitment threshold without a change in firing frequency gain.
Our results demonstrate that GABAA mediated tonic inhibition and glutamate mediated current modulate recruitment threshold and firing behaviour of ocular motoneurons depending on motoneuron size. These synaptic mechanisms, dependent on cell size, could be underlying the positive relationship between threshold and eye position sensitivity reported in ocular motoneurons recorded in alert preparation.
AbstractThe neuronal input–output function depends on recruitment threshold and gain of the firing frequency–current (f–I) relationship. These two parameters are positively correlated in ocular motoneurons (MNs) recorded in alert preparation and inhibitory inputs could contribute to this correlation. Phasic inhibition mediated by γ‐amino butyric acid (GABA) occurs when a high concentration of GABA at the synaptic cleft activates postsynaptic GABAA receptors, allowing neuronal information transfer. In some neuronal populations, low concentrations of GABA activate non‐synaptic GABAA receptors and generate a tonic inhibition, which modulates cell excitability. This study determined how ambient GABA concentrations modulate the input–output relationship of rat oculomotor nucleus MNs. Superfusion of brain slices with GABA (100 μm) produced a GABAA receptor‐mediated current that reduced the input resistance, increased the recruitment threshold and shifted the f–I relationship rightward without any change in gain. These modifications did not depend on MN size. In absence of exogenous GABA, gabazine (20 μm; antagonist of GABAA receptors) abolished spontaneous inhibitory postsynaptic currents and revealed a tonic current in MNs. Gabazine increased input resistance and decreased recruitment threshold mainly in larger MNs. The f–I relationship shifted to the left, without any change in gain. Gabazine effects were chiefly due to MN tonic inhibition because tonic current amplitude was five‐fold greater than phasic. This study demonstrates a tonic inhibition in ocular MNs that modulates cell excitability depending on cell size. We suggest that GABAA tonic inhibition acting concurrently with glutamate receptors activation could reproduce the positive covariation between threshold and gain reported in alert preparation.
Genetic Mechanisms Underlying the Pathogenicity of Cold-Stressed Salmonella enterica Serovar Typhimurium in Cultured Intestinal Epithelial Cells
Authors: Shah Jigna , Desai Prerak T. , Weimer Bart C. 
Published: September 2014

ABSTRACT

Salmonella
encounters various stresses in the environment and in the host during infection. The effects of cold (5°C, 48 h), peroxide (5 mM H
2
O
2
, 5 h) and acid stress (pH 4.0, 90 min) were tested on pathogenicity of
Salmonella
. Prior exposure of
Salmonella
to cold stress significantly (
P
< 0.05) increased adhesion and invasion of cultured intestinal epithelial (Caco-2) cells. This increased
Salmonella
-host cell association was also correlated with significant induction of several virulence-associated genes, implying an increased potential of cold-stressed
Salmonella
to cause an infection. In Caco-2 cells infected with cold-stressed
Salmonella
, genes involved in the electron transfer chain were significantly induced, but no simultaneous significant increase in expression of antioxidant genes that neutralize the effect of superoxide radicals or reactive oxygen species was observed. Increased production of caspase 9 and caspase 3/7 was confirmed during host cell infection with cold-stressed
Salmonella
. Further, a prophage gene,
STM2699
, induced in cold-stressed
Salmonella
and a spectrin gene, SPTAN1, induced in
Salmonella
-infected intestinal epithelial cells were found to have a significant contribution in increased adhesion and invasion of cold-stressed
Salmonella
in epithelial cells.
Genomic Characterization of Non-Mucus-Adherent Derivatives of Lactobacillus rhamnosus GG Reveals Genes Affecting Pilus Biogenesis
Authors: Rasinkangas Pia , Reunanen Justus , Douillard François P. , Ritari Jarmo , Uotinen Virva , Palva Airi , de Vos Willem M. 
Published: September 2014

ABSTRACT

Lactobacillus rhamnosus
GG is one of the best-characterized lactic acid bacteria and can be considered a probiotic paradigm. Comparative and functional genome analysis showed that
L. rhamnosus
GG harbors a genomic island including the
spaCBA-srtC1
gene cluster, encoding the cell surface-decorating host-interacting pili. Here, induced mutagenesis was used to study pilus biogenesis in
L. rhamnosus
GG. A combination of two powerful approaches, mutation selection and next-generation sequencing, was applied to
L. rhamnosus
GG for the selection of pilus-deficient mutants from an enriched population. The isolated mutants were first screened by immuno-dot blot analysis using antiserum against pilin proteins. Relevant mutants were selected, and the lack of pili was confirmed by immunoelectron microscopy. The pilosotype of 10 mutant strains was further characterized by analyzing pilin expression using Western blot, dot blot, and immunofluorescence methods. A mucus binding assay showed that the mutants did not adhere to porcine intestinal mucus. Comparative genome sequence analysis using the Illumina MiSeq platform allowed us to determine the nature of the mutations in the obtained pilus-deficient derivatives. Three major classes of mutants with unique genotypes were observed: class I, with mutations in the
srtC1
gene; class II, with a deletion containing the
spaCBA-srtC1
gene cluster; and class III, with mutations in the
spaA
gene. Only a limited number of collateral mutations were observed, and one of the pilus-deficient derivatives with a deficient
srtC1
gene contained 24 other mutations. This strain, PB12, can be considered a candidate for human trials addressing the impact of the absence of pili.
Arcobacter butzleri in Sheep Ricotta Cheese at Retail and Related Sources of Contamination in an Industrial Dairy Plant
Authors: Scarano Christian , Giacometti Federica , Manfreda Gerardo , Lucchi Alex , Pes Emanuela , Spanu Carlo , De Santis Enrico Pietro Luigi , Serraino Andrea 
Published: September 2014

ABSTRACT

This study aimed to evaluate
Arcobacter
species contamination of industrial sheep ricotta cheese purchased at retail and to establish if the dairy plant environment may represent a source of contamination. A total of 32 sheep ricotta cheeses (1.5 kg/pack) packed in a modified atmosphere were purchased at retail, and 30 samples were collected in two sampling sessions performed in the cheese factory from surfaces in contact with food and from surfaces not in contact with food. Seven out of 32 samples (21.9%) of ricotta cheese collected at retail tested positive for
Arcobacter butzleri
at cultural examination; all positive samples were collected during the same sampling and belonged to the same batch. Ten surface samples (33.3%) collected in the dairy plant were positive for
A. butzleri
. Cluster analysis identified 32 pulsed-field gel electrophoresis (PFGE) patterns. The same PFGE pattern was isolated from more than one ricotta cheese sample, indicating a common source of contamination, while more PFGE patterns could be isolated in single samples, indicating different sources of contamination. The results of the environmental sampling showed that
A. butzleri
may be commonly isolated from the dairy processing plant investigated and may survive over time, as confirmed by the isolation of the same PFGE pattern in different industrial plant surface samples. Floor contamination may represent a source of
A. butzleri
spread to different areas of the dairy plant, as demonstrated by isolation of the same PFGE pattern in different production areas. Isolation of the same PFGE pattern from surface samples in the dairy plant and from ricotta cheese purchased at retail showed that plant surfaces may represent a source of
A. butzleri
postprocessing contamination in cheeses produced in industrial dairy plants.
Chicken Juice Enhances Surface Attachment and Biofilm Formation of Campylobacter jejuni
Authors: Brown Helen L. , Reuter Mark , Salt Louise J. , Cross Kathryn L. , Betts Roy P. , van Vliet Arnoud H. M. 
Published: September 2014

ABSTRACT

The bacterial pathogen
Campylobacter jejuni
is primarily transmitted via the consumption of contaminated foodstuffs, especially poultry meat. In food processing environments,
C. jejuni
is required to survive a multitude of stresses and requires the use of specific survival mechanisms, such as biofilms. An initial step in biofilm formation is bacterial attachment to a surface. Here, we investigated the effects of a chicken meat exudate (chicken juice) on
C. jejuni
surface attachment and biofilm formation. Supplementation of brucella broth with ≥5% chicken juice resulted in increased biofilm formation on glass, polystyrene, and stainless steel surfaces with four
C. jejuni
isolates and one
C. coli
isolate in both microaerobic and aerobic conditions. When incubated with chicken juice,
C. jejuni
was both able to grow and form biofilms in static cultures in aerobic conditions. Electron microscopy showed that
C. jejuni
cells were associated with chicken juice particulates attached to the abiotic surface rather than the surface itself. This suggests that chicken juice contributes to
C. jejuni
biofilm formation by covering and conditioning the abiotic surface and is a source of nutrients. Chicken juice was able to complement the reduction in biofilm formation of an aflagellated mutant of
C. jejuni
, indicating that chicken juice may support food chain transmission of isolates with lowered motility. We provide here a useful model for studying the interaction of
C. jejuni
biofilms in food chain-relevant conditions and also show a possible mechanism for
C. jejuni
cell attachment and biofilm initiation on abiotic surfaces within the food chain.
Survival of Escherichia coli Cells on Solid Copper Surfaces Is Increased by Glutathione
Authors: Große Cornelia , Schleuder Grit , Schmole Christin , Nies Dietrich H. 
Published: September 2014

ABSTRACT

Bacteria are rapidly killed on solid copper surfaces, so this material could be useful to limit the spread of multiple-drug-resistant bacteria in hospitals. In
Escherichia coli
, the DNA-protecting Dps protein and the NADH:ubiquinone oxidoreductase II Ndh were not involved in tolerance to copper ions or survival on solid copper surfaces. Decreased copper tolerance under anaerobic growth conditions in the presence of ascorbate and with melibiose as the carbon source indicated that sodium-dependent symport systems may provide an import route for Cu
I
into the cytoplasm. Glutathione-free Δ
copA
Δ
gshA
double mutants of
E. coli
were more rapidly inactivated on solid copper surfaces than glutathione-containing wild-type cells. Therefore, while DNA protection by Dps was not required, glutathione was needed to protect the cytoplasm and the DNA against damage mediated by solid copper surfaces, which may explain the differences in the molecular mechanisms of killing between glutathione-containing Gram-negative and glutathione-free Gram-positive bacteria.
Effects of Electroacupuncture on Bone Mass and Cathepsin K Expression in Ovariectomised Rats
Authors: Zhou Jun , Li Xinhong , Liao Ying , Feng Weibing , Guo Xin 
Published: September 2014

Objective To characterise the effects of early and late electroacupuncture (EA) treatment on serum 17β-oestradiol (E2), C-terminal cross-linking telopeptide of type I collagen (CTX-I), bone mineral density (BMD), biomechanical bone strength and mRNA expression of cathepsin K in ovariectomised (OVX) rats. Methods Sixty Sprague-Dawley rats underwent ovariectomy (n=40) or sham surgery (n=20) and were randomly divided into two batches. Batch 1 (n=30) consisted of 10 sham-operated rats (Sham-0 group) and 20 OVX rats: half commenced EA immediately (early EA group, n=10) and half were left untreated (OVX-0 group, n=10). Batch 2 (n=30) consisted of 10 sham-operated rats (Sham-12 group) and 20 OVX rats: half commenced EA treatment 12 weeks after ovariectomy (late EA group, n=10) and half were left untreated (OVX-12 group, n=10). Rats in batches 1 and 2 were killed after 12 and 24 weeks, respectively. Serum E2, CTX-I, BMD, bone strength and cathepsin K expression were determined by ELISA, dual energy X-ray absorptiometry, biomechanical assessment and qRT-PCR, respectively. Results Both early and late EA treatment increased serum E2 levels, reduced serum CTX- I levels and increased BMD and bone strength of the L5 vertebral body in OVX rats. Although early EA treatment similarly increased BMD and bone strength of the femur, late EA treatment did not. However, both early and late EA treatment reduced mRNA expression of cathepsin K in OVX rats. Conclusions Early EA completely prevented and late EA partially prevented bone loss and deterioration of bone strength in OVX rats. The timing of initiation of EA treatment may be an important consideration for optimisation of effects. The influence of EA on bone strength appears to be at least partially mediated through regulation of the expression of cathepsin K.
Acupuncture for Retained Placenta: A Retrospective Case Series
Authors: Djakovic Ivka , Bilic Nada 
Published: September 2014

Background A placenta is considered to be retained when it remains undelivered 30 or 60 min after the birth of the baby following active or physiological management of the third stage of labour, respectively. It can be life threatening for the mother. Methods We retrospectively examined the influence of acupuncture on the delivery of retained placentas in the third stage of labour in 70 women. In all cases the third stage of labour was actively managed, and acupuncture was provided 30 min after delivery at points KI16 and SP6 for 15 min. Results After acupuncture 77% of placentas separated successfully. In 10% of cases some retained placental tissue was detected and manual removal of the avulsed cotyledon was performed, while in 13% the entire placenta was retained and manual removal of the placenta under general anaesthesia was necessary. Conclusions Acupuncture may help to facilitate placental separation but further controlled trials are needed.