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1.
Lipopolysaccharide and cytokines modulate leukotriene (LT)B4 and LTC4 production by porcine endometrial endothelial cells 下载免费PDF全文
Uterine inflammatory response is mediated by inflammatory mediators including eicosanoids and cytokines produced by immune and endometrial cells. Interactions between lipopolysaccharide (LPS) and cytokines, and leukotrienes (LTs) in endothelium, important for the host defence during the inflammation, are unknown. We studied the effect of LPS, tumour necrosis factor (TNF)‐α, interleukin (IL)‐1β, IL‐4 and IL‐10 on 5‐lipooxygenase (5‐LO), LTA4 hydrolase (LTAH) and LTC4 synthase (LTCS) mRNA and protein expression, LTB4 and LTC4 release from porcine endometrial endothelial cells, and cell viability. For 24 hr, cells were exposed to LPS (10 or 100 ng/ml of medium) and cytokines (each 1 or 10 ng/ml). 5‐LO mRNA/protein expression augmented after incubation with larger doses of LPS, TNF‐α, IL‐4 and IL‐10 and smaller dose of IL‐1β. Larger dose of TNF‐α, smaller doses of LPS and IL‐1β and both doses of IL‐10 increased LTAH mRNA/protein expression. LTAH protein content was up‐regulated by larger dose of LPS, but it was reduced in response to both doses of IL‐4. LTCS mRNA expression was elevated by larger doses of LPS, IL‐4 and IL‐10 or both doses of TNF‐α and IL‐1β. LTCS protein level increased after treatment with both doses of IL‐1β, IL‐4 and IL‐10, smaller dose of LPS and larger dose of TNF‐α. Both doses of LPS and larger doses of TNF‐α and IL‐10 increased LTB4 release. LPS, IL‐1β and IL‐10 at smaller doses, or TNF‐α and IL‐4 at larger doses stimulated LTC4 release. Smaller doses of TNF‐α and IL‐1β or both doses of IL‐4 enhanced the cell viability. This work provides new insight on the participation of LPS, TNF‐α, IL‐1β, IL‐4 and IL‐10 in LTB4 and LTC4 production/release from porcine endometrial endothelial cells, and the effect of above factors on these cells viability. The used cellular model gives the possibility to further establish the interactions between inflammatory mediators. 相似文献
2.
Identification of genic SSRs in jute (Corchorus capsularis,Malvaceae) and development of markers for phenylpropanoid biosynthesis genes and regulatory genes 下载免费PDF全文
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Birgit Eickler Jana Kleen F. Taube 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):39-49
Abstract In feeding studies, red clover (RC) influenced positively the N utilization by ruminants. A relationship between polyphenol oxidase (PPO) activity and forage quality has not been established. Our objective was to investigate seasonal, site, genotype, and management effects on specific PPO activity in RC in three experiments under field conditions, and relate the activity to forage-quality parameters. In Experiment 1, six RC genotypes at two study sites were submitted to a 3-cut system. Specific PPO activity, forage quality, and vegetation stage were determined. PPO activity varied between harvest and study sites, with genotypes differing up to 3-fold in PPO activity within harvests. The specific PPO activity, forage quality, and vegetation stage in RC subjected to 5-cut system and grazing (Experiment 2) were determined. Additionally, in Experiment 3, cutting frequency in RC swards including mechanical stress (rolling) was investigated. The induction of PPO activity in RC by grazing or mechanical stress (Experiments 2 and 3) increased the activity up to 2.5-fold compared with RC at similar vegetation stage submitted to the 5-cut system. Mechanical stress induced by grazing or rolling, and seasonal differences, seem to have a larger influence on specific PPO activity than does the genotype effect observed in Experiment 1. For forage quality, an increased specific PPO activity explained 29–46% of the reduction in protein fraction ‘A’ content (non-protein N) in the cutting systems in Experiments 2 and 3. Other CP fractions achieved a lower relation. Furthermore, the precipitation-to-temperature ratio preceeding a harvest explained 63% of the variation in the specific PPO activity. In conclusion, the PPO activity in RC is induced by grazing and rolling. Whereas weather conditions preceeding a harvest showed a large influence, genotype influence had only minor relevance. These results may have implications for regional harvest management towards efficient N utilization by ruminants. 相似文献
5.
In the adult fish trematode Crepidostomum metoecus (Braun, 1900), four types of sensory receptors were observed inside the forebody tegument and one type beneath the tegument basal lamina. Two types of sensory receptors extend through the thickness of tegument and have a free cilium inside a pit (types I and II). Two types (III and IV) are nonciliate and entirely intra-tegumental in location. Type IV receptor with large horizontal and thin vertical rootlets was described earlier in aspidogastreans only. Below the basal lamina, nerve endings in close association with muscle fibres, comparable with those in the Aspidogastrea, were detected. 相似文献
6.
Vilcek S Mojzisová J Bajová V Paulík S Strojný L Durkovic B Hipíková V 《Acta veterinaria Hungarica》2003,51(2):229-236
A serological survey for bovine viral diarrhoea virus (BVDV) antibodies on a collection of 1295 serum samples obtained from 6-12 months old cattle originating from 45 farms in Slovakia was carried out. On 13 farms more than 90% of the examined animals were seropositive, on 14 farms 71-90% seroprevalence was observed, on 13 farms only 50-70% animals were found to be positive for BVDV antibodies, while the remaining 5 farms showed fewer than 50% seropositive animals. The average incidence of BVDV antibodies (around 70%) was similar as determined 30 years ago. Of 84 serum samples from seronegative animals originating from 14 farms in which 70-98% seropositivity was observed, six were positive in Ag-BVDV ELISA indicating persistently infected (PI) cattle. On a farm to which animals were imported from abroad, a BVD outbreak was observed. Of 110 animals tested, four were positive in Ag-ELISA indicating the presence of PI cattle on this farm. Genetic typing of two isolates from imported animals performed by RT-PCR (324/326 primers from 5'-UTR), sequencing of PCR products and computer-assisted phylogenetic analysis revealed that they belong to BVDV-1 h group. 相似文献
7.
The present study was designed to examine the influence of gonadotrophins treatment on the ovarian morphology changes and plasma concentrations of steroid hormones in peripheral blood. The experiment was performed on sexually pubertal gilts (Large White x Landrace) of similar age (7-8 months) and body mass (100-110 kg) with two controlled subsequent estrous cycles. The animals were randomly divided into four groups: two control consisting of pigs with the luteal phase (n = 9, the 10th day of the estrous cycle) and the follicular phase (n = 6, the 20th day of the estrous cycle) and two experimental ones consisting of animals with both mentioned periods (n = 7 and n = 9) treated with gonadotrophins (PMSG and hCG). The gilts in the luteal phase were injected (s.c.) with gonadotrophins at a daily dose of PMSG 400 and hCG 200 IU from the 16th to the 27th day (the 6th day of the next estrous cycle). The gilts in the follicular phase, were injected with the same dose of gonadotrophins but from the 8th to the 19th day of the estrous cycle. Plasma concentrations of P4, A4, T, E1, E2 and metabolite of PGF2 alpha-PGFM were determined by radioimmunoassay (RIA) method. Injections of PMSG and hCG in both experimental groups produced several times enlarged: weight, size and volume of ovaries and alterations in a number of structural elements as compared with those found in the control animals. The morphological elements presented in ovaries: corpora haemorrhagica, corpora lutea, regular and atretic follicles and first of all cysts by distinctly differentiation thickness of the walls are characteristic for cystic ovarian degeneration. Plasma concentrations all determined hormones after gonadotrophins treatment in experimental groups were increased except E1 (insignificant decrease) in luteal phase as compared with those found in the control groups. Statistically significant increase (p < 0.001) in plasma concentrations of P4, A4, and T in both experimental groups and E2 (p < 0.001) in luteal phase were noted. In peripheral plasma concentrations increase of E1 and E2 in follicular phase of the estrous cycle were insignificant. 相似文献
8.
ABSTRACT Ontogeny of the invasion process by Colletotrichum acutatum and C. fragariae was studied on petioles and stolons of the strawberry cultivar Chandler using light and electron microscopy. The invasion of host tissue by each fungal species was similar; however, each invasion event occurred more rapidly with C. fragariae than with C. acutatum. Following cuticular penetration via an appressorium, subsequent steps of invasion involved hyphal growth within the cuticle and within the cell walls of epidermal, subepidermal, and subtending cells. Both species of fungi began invasion with a brief biotrophic phase before entering an extended necrotrophic phase. Acervuli formed once the cortical tissue had been moderately disrupted and began with the development of a stroma just beneath the outer periclinal epidermal walls. Acervuli erupted through the cuticle and released conidia. Invasion of the vascular tissue typically occurred after acervulus maturation and remained minimal. Chitin distribution in walls of C. fragariae was visualized with gold-labeled wheat germ agglutinin. The outer layer of bilayered walls of conidia, germ tubes, and appressoria contained less chitin than unilayered hyphae in planta. 相似文献
9.
Nitrogen-fixing species can dramatically increase soil acidity and organic matter content, and potentially alter biogeochemical P dynamics. We compared ecosystem P cycling in adjacent stands of N2-fixing red alder (Alnus rubra Bong.) and non-fixing Douglas-fir (Pseudotsuga menziesii Franco) in order to determine whether P-cycling rates within stands were related to soil P forms as measured by sequential P fractionation. Above-ground annual P uptake was 61% greater in the red alder stand, although soil available P, as measured by Bray (NH4F–HCl) extraction, was only 10% of that found in the Douglas-fir stand. Total ecosystem P in the alder stand was only 69% of that found in the Douglas-fir stand, and could indicate a pre-establishment difference between stands. However, the percentage of total soil P released by Bray or NaOH extraction was also lower in the alder stand, which suggests that differences in total P alone did not control the patterns observed in P fractions. Concentrations of inorganic P sorbed to Fe and Al minerals and contained in Fe minerals and apatite were greater under Douglas-fir, while organic P was slightly greater under red alder. While fluxes of P in litterfall, uptake and resorption were 94, 60 and 292% higher in the alder stand, soil extractable fractions meant to represent available P were lower under alder. Static measures of available P do not appear to adequately reflect P supply, and the development of techniques to assess P turnover is needed to better understand cycling and plant availability of P. 相似文献
10.
Michal Vla?ín Robert Luká? Zuzana Kauerová Pavel Kohout Josef Ma?ek Eli?ka Bartheldyová ?těpán Koudelka Zina Korvasová Jana Plocková Nikola Hronová Jaroslav Turánek 《Canadian journal of veterinary research》2014,78(2):133-139
Specific contrast ultrasound is widely applied in diagnostic procedures on humans but remains underused in veterinary medicine. The objective of this study was to evaluate the use of microbubble-based contrast for rapid ultrasonographic diagnosis of thrombosis in small animals, using male New Zealand white rabbits (average weight about 3.5 kg) as a model. It was hypothesized that the use of microbubble-based contrast agents will result in a faster and more precise diagnosis in our model of thrombosis. A pro-coagulant environment had been previously established by combining endothelial denudation and external vessel wall damage. Visualization of thrombi was achieved by application of contrast microbubbles [sterically stabilized, phospholipid-based microbubbles filled with sulfur hexafluoride (SF6) gas] and ultrasonography. As a result, rapid and clear diagnosis of thrombi in aorta abdominalis was achieved within 10 to 30 s (mean: 17.3 s) by applying microbubbles as an ultrasound contrast medium. In the control group, diagnosis was not possible or took 90 to 180 s. Therefore, sterically stabilized microbubbles were found to be a suitable contrast agent for the rapid diagnosis of thrombi in an experimental model in rabbits. This contrast agent could be of practical importance in small animal practice for rapid diagnosis of thrombosis. 相似文献