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461.
Evolutionary morphological and physiological differences between browsers and grazers contribute to species‐specific digestion efficiency of food resources. Rumen microbial community structure of browsers is supposedly adapted to characteristic nutrient composition of the diet source. If this assumption is correct, domesticated ruminants, or grazers, are poor model animals for assessing the nutritional value of food consumed by browsing game species. In this study, typical spring and summer foods of the European moose (Alces alces) were combined with rumen fluid collected from both dairy cows (Bos taurus) and from moose, with the aim of comparing fermentation efficiency and microbial community composition. The nutritional value of the food resources was characterized by chemical analysis and advanced in vitro measurements. The study also addressed whether or not feed evaluation based on in vitro techniques with cattle rumen fluid as inoculum could be a practical alternative when evaluating the nutritional value of plants consumed by wild browsers. Our results suggest that the fermentation characteristics of moose spring and summer food are partly host‐specific and related to the contribution of the bacterial phyla Firmicutes and Bacteriodetes to the rumen microbial community. Host‐specific adaptations of the ruminal microbial community structure could be explained from the evolutionary adaptations related to feeding habitats and morphophysiological differences between browsers and grazers. However, the observed overall differences in microbial community structure could not be related to ruminal digestion parameters measured in vitro. The in vitro evaluation of digestion efficiency reveals that equal amounts of methane were produced across all feed samples regardless of whether the ruminal fluid was from moose or dairy cow. The results of this study suggested that the nutritional value of browsers' spring and summer food can be predicted using rumen fluid from domesticated grazers as inoculum in in vitro assessments of extent of digestion when excluding samples of the white water lily root, but not of fermentation characteristics as indicated by the proportions of individual fermentation fatty acids to the total of volatile fatty acids.  相似文献   
462.
We use the dissipative particle dynamics (DPD) method to simulate the non-Newtonian electroosmotic flow (EOF) through nanochannels. Contrary to a large amount of past computational efforts dedicated to the study of EOF profile, this work pays attention to the EOF of non-Newtonian fluids, which has been rarely touched in past publications. Practically, there are many MEMS/NEMS devices, in which the EOF behaviour should be treated assuming both non-continuum and non-Newtonian conditions. Therefore, our concern in this work is to simulate the EOF through nanochannels considering both non-Newtonian fluid properties and non-continuum flow conditions. We have chosen DPD as our working tool because it provides several important advantages comparing with the classical time consuming molecular dynamics method. Using the DPD method, we explore the effect of a few important fluid properties and nanochannel parameters on the EOF behaviour and the resulting flow rate magnitudes. Our investigation will result in a number of findings, which have not been reported in past research works.  相似文献   
463.
Determinative associations may exist between costimulatory molecule gene polymorphisms with a variety of post hematopoietic stem cell transplantation (HSCT) viral related clinical outcomes especially acute graft versus host disease (aGVHD). Therefore in this study the associations between costimulatory molecule gene polymorphisms including: cytotoxic T-lymphocyte antigen-4 (CTLA4), programmed cell death-1 (PD-1), inducible T cell costimulator (ICOS), and cluster differentiation 28 (CD28) with active cytomegalovirus (CMV) infection were evaluated in HSCT patients. The 72 allogeneic HSCT patients with and without aGVHD were enrolled in this cross sectional study between years: 2004–2011. The single nucleotide polymorphisms in loci of the costimulatory molecules including: CTLA4 gene (?318 C/T, 1722 T/C, 1661 A/G, +49 A/G), PD-1 gene (PD-1.3 A/G, PD-1.9 C/T), ICOS gene (1720 C/T), and CD28 gene (+17 C/T) were analyzed in studied HSCT patients by PCR-RFLP methods. The active CMV infection was evaluated in fresh EDTA-treated blood samples of each allogeneic HSCT patients by CMV antigenemia kit according to manufacturer’s instruction. Active CMV infection was found in 11 of 72 (15.27 %) of allogeneic HSCT patients. The T allele and TT genotype of the CD28 +17 C/T were significantly higher frequency in active CMV infected allogeneic HSCT patients experienced aGVHD. The G allele and GG genotype of the CTLA4 ?1661 A/G were significantly higher frequent in active CMV infected allogeneic HSCT patients experienced low grade of aGVHD. Finally, finding of significant associations between CD28 +17 C/T and CTLA4 ?1661 A/G genotypes with CMV active infection in allogeneic HSCT patients experienced aGVHD emphasize on the importance of the genetic pattern of costimulatory genes in outcomes of active CMV infection in HSCT patients needs completed studies.  相似文献   
464.
The ladybird Hippodamia variegata Goeze is a widespread species found in many parts of the world. It is an efficient predator which feeds on a wide range of pests, specially aphids and other sap feeders. Mass rearing of this predator, in order to use in biological control programmes, entails a great deal of difficulties, among which are the aspects associated with nutrition. Applying artificial diets is of a great importance in mass rearing of biological control agents. We investigated the use of 15 artificial diets that included three separated experiments, in order to rear larval stages of this ladybird. The survival rate and developmental time were assessed on each treatment. The survival rate of the larvae on best diet was 53.30, 93.33, and 93.33% in different experiments. The developmental time in the experiment 1, 2 and 3 for the larva fed on the Aphis fabae was 15.59, 15.51 and 15.94, respectively, but when nourished by the best artificial diets, this factor was 26.59, 26.60 and 20.59, respectively. Developmental time for the larvae fed on A. fabae was significantly shorter than developmental time of larvae on artificial diets. Our results showed that artificial diets have the capacity to support the larval development to adulthood.  相似文献   
465.
The root-knot nematode Meloidogyne spp. includes important plant pathogens worldwide. This study has considered nematode Meloidogyne javanica second stage larvae activity in the extracts of Pseudomonas fluorescens strains UTPF5 and cytotoxic effect of the strain on the nematode. The movement of second stage larvae of nematodes in water agar medium at four concentrations of bacterial extracts and second stage larvae mortality rate of hatching nematode and bacterial strains in vitro were affected. Different concentrates of the strain UTPF5 effect nematode larvae movement and disposal of the same. Bacterial extraction kills almost 100% of the larvae hatching after 24?h and a complete ban on egg hatch of biocontrol nematodes and nematode indicated that root-knot nematode larvae movement on the right attract the bacteria P. fluorescens to extract in the first place.  相似文献   
466.
467.
Patients with Huntington's disease (HD) and transgenic mouse models of HD show neuronal loss in the striatum as a major feature, which contributes to cognitive and motor manifestations. Reduced expression of the neurotrophin brain‐derived neurotrophic factor (BDNF) in striatal afferents may play a role in neuronal loss. How progressive loss of BDNF expression in different cortical or subcortical afferents contributes to striatal atrophy and behavioral dysfunction in HD is not known, and may best be determined in animal models. We compared age‐dependent alterations of BDNF mRNA expression in major striatal afferents from the cerebral cortex, thalamus and midbrain in the R6/2 transgenic mouse model of HD. Corresponding changes in striatal morphology were quantified using unbiased stereology. Changes in motor behavior were measured using an open field, grip strength monitor, limb clasping and a rotarod apparatus. BDNF expression in cortical limbic and midbrain striatal afferents is reduced by age 4 weeks, prior to onset of motor abnormalities. BDNF expression in motor cortex and thalamic afferents is reduced by 6 weeks, coinciding with early motor dysfunction and reduced striatum volume. BDNF loss in afferents progresses until death at 13–15 weeks, correlating with progressive striatal neuronal loss and motor abnormalities. Mutant huntingtin protein expression in R6/2 mice results in progressive loss of BDNF in both cortical and subcortical striatal afferents. BDNF loss in limbic and dopaminergic striatal inputs may contribute to cognitive/psychiatric dysfunction in HD. Subsequent BDNF loss in cortical motor and thalamic afferents may accelerate striatal degeneration, resulting in progressive involuntary movements.  相似文献   
468.
The discovery and development of antimicrobial agents that do not give rise to resistance remains an ongoing challenge. Our efforts in this regard continue to reveal new potential therapeutic agents with differing physicochemical properties while retaining the effective N,N-dichloroamine pharmacophore as the key antimicrobial warhead. In this Letter, we disclose agents containing polyol units as a water solubilizing group. These sulfonyl-polyol agents show broad spectrum bactericidal and virucidal activity. These compounds show 1h MBC’s of 16–512 μg/mL against Escherichia coli and 4–256 μg/mL against Staphylococcus aureus at neutral pH, and 1-h IC50’s of 4.5–32 μM against Adenovirus 5 and 0.7–3.0 μM against Herpes simplex virus 1. The lead compounds were tested in a tissue culture irritancy assay and showed only minimal irritation at the highest concentrations tested.  相似文献   
469.
Ionizing radiation significantly alters the structure and function of microvasculature, which regulates delivery of oxygen to brain tissue. Previous experimental and modeling studies have shown that tissue oxygenation patterns are significantly different in irradiated normal tissue compared to age-matched controls, and the differences are apparent as early as 3 days postirradiation. However, oxygen delivery to irradiated tissue recovers within 6 months postirradiation. Changes in perfusion and oxygenation were studied in a bilaterally (both cerebral hemispheres) and unilaterally (only one hemisphere) irradiated mouse brain model at 6 and 24 h as well as 3, 7, 30, 60 and 120 days postirradiation. The results indicate that significant changes in the number of perfused vessels (as measured by fluorescent DiOC(7) staining) and anatomical vessels (as indicated by CD31 immunohistochemical staining) and tissue oxygenation (by immunohistochemical detection of a fluorescently conjugated monoclonal antibody to EF5) are most pronounced at 3 days postirradiation, while a degree of recovery is observed at later times. However, in the unilaterally irradiated animals, both irradiated and unirradiated (out-of-field) cerebral hemispheres showed similarly significant changes in oxygenation and/or perfusion compared to unirradiated controls. Anti-TNFA treatment inhibited radiation-induced local as well as abscopal effects in the brain tissue.  相似文献   
470.
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