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91.

Aim

The objective of this study was to describe the French practice of hypothermia treatment (HT) in full-term newborns with hypoxic-ischemic encephalopathy (HIE) and to analyze the deviations from the guidelines of the French Society of Neonatology.

Materials and Methods

From May 2010 to March 2012 we recorded all cases of HIE treated by HT in a French national database. The population was divided into three groups, "optimal HT" (OHT), “late HT” (LHT) and “non-indicated” HT (NIHT), according to the guidelines.

Results

Of the 311 newborns registered in the database and having HT, 65% were classified in the OHT group, 22% and 13% in the LHT and NIHT groups respectively. The severity of asphyxia and HIE were comparable between newborns with OHT and LHT, apart from EEG. HT was initiated at a mean time of 12 hours of life in the LHT group. An acute obstetrical event was more likely to be identified among newborns with LHT (46%), compared to OHT (34%) and NIHT (22%). There was a gradation in the rate of complications from the NIHT group (29%) to the LHT (38%) group and the OHT group (52%). Despite an insignificant difference in the rates of death or abnormal neurological examination at discharge, nearly 60% of newborns in the OHT group had an MRI showing abnormalities, compared to 44% and 49% in the LHT and NIHT groups respectively.

Conclusion

The conduct of the HT for HIE newborns is not consistent with French guidelines for 35% of newborns, 22% being explained by an excessive delay in the start of HT, 13% by the lack of adherence to the clinical indications. This first report illustrates the difficulties in implementing guidelines for HT and should argue for an optimization of perinatal care for HIE.  相似文献   
92.
The effects of cyanide and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) on photosynthesis and respiration of intact chlorophyllic moss (Funaria hygrometrica) spore was investigated. Thirty micromolar cyanide strongly inhibited dark respiration, was without effect on photosynthesis at high light intensities (above the saturation plateau values), and stimulated photosynthesis at low light intensities (below the saturation plateau values). Three hundred nanomolar DCMU inhibited the photosynthesis and was without effect, even under light conditions, on the dark respiration. It seems likely, therefore, that in the chlorophyllic moss spore the cytochrome oxidase pathway is not functioning under high light intensities unless the photosynthesis is inhibited by DCMU.  相似文献   
93.
94.
The aim of this study was to determine the best processing conditions to extract Brazilian green propolis using a supercritical extraction technology. For this purpose, the influence of different parameters was evaluated such as S/F (solvent mass in relation to solute mass), percentage of co-solvent (1 and 2% ethanol), temperature (40 and 50°C) and pressure (250, 350 and 400 bar) using supercritical carbon dioxide. The Global Yield Isotherms (GYIs) were obtained through the evaluation of the yield, and the chemical composition of the extracts was also obtained in relation to the total phenolic compounds, flavonoids, antioxidant activity and 3,5-diprenyl-4-hydroxicinnamic acid (Artepillin C) and acid 4-hydroxycinnamic (p-coumaric acid). The best results were identified at 50°C, 350 bar, 1% ethanol (co-solvent) and S/F of 110. These conditions, a content of 8.93±0.01 and 0.40±0.05 g/100 g of Artepillin C and p-coumaric acid, respectively, were identified indicating the efficiency of the extraction process. Despite of low yield of the process, the extracts obtained had high contents of relevant compounds, proving the viability of the process to obtain green propolis extracts with important biological applications due to the extracts composition.  相似文献   
95.
The immunopathologic and inflammatory mechanisms involved in periodontal disease (PD) include the participation of host resident, inflammatory cells and chemical mediators. Metalloproteinases (MMPs) and nitric oxide (NO) play essential role in extracellular matrix turnover of periodontal tissue destruction. In this study, by means of RT-PCR through semi-quantitative densitometric scanning methods, the expression of MMPs -2 and -9 and inducible NO synthase (iNOS) was temporally and spatially investigated during the destructive mechanisms of experimentally induced PD in rats. Samples from different periods were microscopically analyzed and compared with the contralateral side (control). Our results showed significant expression of MMP-9 and iNOS in tissues affected by PD, as compared with controls, three days after PD induction, simultaneously with the beginning of alveolar bone loss. At 7 days post induction, only the MMP-9 mRNA presented a significantly higher expression, as compared with the respective controls. Thus, in the rat ligature-induced PD, MMP-9 and iNOS might importantly participate in the early stages of the disease, including inflammatory cell migration, tissue destruction and alveolar bone resorption. Also, we may suggest that the exuberant presence of PMNs may be related to the important expression of iNOS and MMP-9 found at 3 days post induction.  相似文献   
96.
The horn fly, Haematobia irritans (L.) (Diptera: Muscidae), is a cosmopolitan livestock pest that has caused a great negative impact on the animal production sector throughout the world. Here, we describe 10 polymorphic microsatellite loci isolated from H. irritans. The number of alleles found ranged from two to eight per locus and the expected heterozygosity from 0.1421 to 0.7702. These loci are potentially useful for the fine-scale genetic characterization of horn fly populations and provide fundamental information for pest management and planning of control programs.  相似文献   
97.
We provide a detailed comparative study of floral ontogeny and vasculature in Xyridaceae, including XyrisAbolboda and Orectanthe. We evaluate these data in the context of a recent well-resolved phylogenetic analysis of Poales to compare floral structures within the xyrid clade (Xyridaceae and Eriocaulaceae). Xyrids are relatively diverse in both flower structure and anatomy; many species incorporate diverse and unusual floral structures such as staminodes and stylar appendages. Xyridaceae possess three generally epipetalous stamens in a single whorl; the “missing” stamen whorl is either entirely absent or transformed into staminodes. Fertile stamens each receive a single vascular bundle diverged from the median petal bundle. In Xyris, the stamen bundle diverges at the flower base, but it diverges at upper flower levels in both Abolboda and Orectanthe. In species of Abolboda that possess staminodes, staminode vasculature is closely associated with the lateral vasculature of each petal. Despite the likely sister-group relationship between Eriocaulaceae and Xyridaceae, our character optimization indicates that the stylar appendages that characterize some Xyridaceae (except Xyris and Achlyphila) are non-homologous with those of some Eriocaulaceae. On the other hand, it remains equivocal whether the loss of a fertile outer androecial whorl occurred more than once during the evolutionary history of the xyrid clade; this transition occurred either once followed by a reversal to fertile stamens in Eriocauloideae and staminodes in some Xyridaceae, or twice independently within both Xyridaceae and Eriocaulaceae.  相似文献   
98.

Background

Lipopolysaccharide (LPS)-triggered Toll-like receptor (TLR) 4-signalling belongs to the key innate defence mechanisms upon infection with Gram-negative bacteria and triggers the subsequent activation of adaptive immunity. There is an active crosstalk between TLR4-mediated and other signalling cascades to secure an effective immune response, but also to prevent excessive inflammation. Many pathogens induce signalling cascades via secreted factors that interfere with TLR signalling to modify and presumably escape the host response. In this context heterotrimeric G proteins and their coupled receptors have been recognized as major cellular targets. Toxigenic strains of Gram-negative Pasteurella multocida produce a toxin (PMT) that constitutively activates the heterotrimeric G proteins G??q, G??13 and G??i independently of G protein-coupled receptors through deamidation. PMT is known to induce signalling events involved in cell proliferation, cell survival and cytoskeleton rearrangement.

Results

Here we show that the activation of heterotrimeric G proteins through PMT suppresses LPS-stimulated IL-12p40 production and eventually impairs the T cell-activating ability of LPS-treated monocytes. This inhibition of TLR4-induced IL-12p40 expression is mediated by G??i-triggered signalling as well as by G?|?-dependent activation of PI3kinase and JNK. Taken together we propose the following model: LPS stimulates TLR4-mediated activation of the NF?B-pathway and thereby the production of TNF-??, IL-6 and IL-12p40. PMT inhibits the production of IL-12p40 by G??i-mediated inhibition of adenylate cyclase and cAMP accumulation and by G?|?-mediated activation of PI3kinase and JNK activation.

Conclusions

On the basis of the experiments with PMT this study gives an example of a pathogen-induced interaction between G protein-mediated and TLR4-triggered signalling and illustrates how a bacterial toxin is able to interfere with the host??s immune response.  相似文献   
99.
100.
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