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91.
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Cláudio de Góis Nery Fernando Stefanato Buranello Cícero Pereira Renata Cantisani Di Francesco 《Revista brasileira de otorrinolaringologia (English ed.)》2011,77(1):84-87
Abnormalities in craniofacial morphology are associated with Eustachian tube dysfunction and otitis media with effusion (OME).Aim: to evaluate the relationship between facial pattern and craniofacial growth direction, and OME in children with enlarged tonsils and adenoids (ETA).Methods: Clinical prospective survey in 79 children (41 male and 38 female), ranging from 4 to 10 years of age, with tonsil and adenoid enlargement (Brodsky's grades III and IV). Forty children presented with OME (study group) and 39 did not (control group). Cephalometric analysis was used to determine the facial pattern.Results: There was no correlation observed between facial pattern and OME (c 2 = 0.25 p = 0.88). Facial Axis was larger in the OME group (F(1.75) = 3.68 p = 0.05) and the Lower Anterior Facial height was smaller (F(1. 75) = 3.99 p = 0.05) in children with otitis media with effusion.Conclusions: There was no correlation between OME and facial pattern in children with ETA although a more horizontal facial growth direction, and a smaller lower anterior facial height was observed consistently among subjects in this group. This suggests that abnormal positioning of the eustachian tube influences the development of OME in children with ETA. 相似文献
93.
Human α-synuclein (α-Syn) is instrumental in maintaining homeostasis of monoamine neurotransmitters in brain, through its trafficking, and regulation of the cell surface expression and, thereby, activity of dopamine, serotonin and norepinephrine transporters. Here we have investigated whether other members of the synuclein family of proteins, γ-synuclein (γ-Syn) and β-synuclein (β-Syn) can similarly modulate the serotonin transporter (SERT). In Ltk− cells co-transfected with SERT and γ-Syn, γ-Syn reduced [3H]5-HT uptake, in a manner dependent on its expression levels. The decrease in SERT activity was via decreased Vmax of the transporter, without change in Km, compared to cells expressing only SERT. By contrast, β-Syn co-expression failed to alter SERT uptake activity, and neither the Vmax nor the Km was changed in the presence of β-Syn. γ-Syn modulation of SERT was only partial, with a maximal ∼27% decrease in SERT activity seen even at high expression levels of γ-Syn. By contrast, α-Syn attenuated SERT activity by ∼65% at identical expression levels as γ-Syn. Co-immunoprecipitation studies showed the presence of heteromeric protein:protein complexes between γ-Syn or α-Syn and SERT, while β-Syn failed to physically interact with SERT. Both α-Syn and γ-Syn colocalized with SERT in rat primary raphae nuclei neurons. These studies document a novel physiological role for γ-Syn in regulating 5-HT synaptic availability and homeostasis, and may be of relevance in depression and mood disorders, where SERT function is dysregulated. 相似文献
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Artificial metalloenzymes based on biotin-avidin technology for the enantioselective reduction of ketones by transfer hydrogenation 下载免费PDF全文
Letondor C Humbert N Ward TR 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(13):4683-4687
Most physiological and biotechnological processes rely on molecular recognition between chiral (handed) molecules. Manmade homogeneous catalysts and enzymes offer complementary means for producing enantiopure (single-handed) compounds. As the subtle details that govern chiral discrimination are difficult to predict, improving the performance of such catalysts often relies on trial-and-error procedures. Homogeneous catalysts are optimized by chemical modification of the chiral environment around the metal center. Enzymes can be improved by modification of gene encoding the protein. Incorporation of a biotinylated organometallic catalyst into a host protein (avidin or streptavidin) affords versatile artificial metalloenzymes for the reduction of ketones by transfer hydrogenation. The boric acid.formate mixture was identified as a hydrogen source compatible with these artificial metalloenzymes. A combined chemo-genetic procedure allows us to optimize the activity and selectivity of these hybrid catalysts: up to 94% (R) enantiomeric excess for the reduction of p-methylacetophenone. These artificial metalloenzymes display features reminiscent of both homogeneous catalysts and enzymes. 相似文献
96.
Enrique Casalino Donia Bouzid Stephanie Antoniol Philippe Kenway Laurent Pereira Christophe Choquet Emergency Department Study Group on Respiratory Viruses 《Internal and emergency medicine》2018,13(5):673-678
To evaluate the impact of an influenza vaccination (IV) coverage (IVC) in a vaccination campaign of an Emergency Department (EDVC) and its impact on ED time interval quality indicators. We conducted a 4 year observational study, with an intervention during the 4th year. IVC was calculated during pre-and early-epidemic periods. During the final period, a 12 weeks EDVC was implemented. Physicians and nurses were trained and sensitized in the importance of vaccination, and their role in the prevention of severe forms of influenza was reinforced. The vaccine was proposed by physicians and nurses, and delivered by them. Repeated measures ANOVA is a validated method for related not independent groups (https://statistics.laerd.com/statistical-guides/repeated-measures-anova-statistical-guide.php). Overall, IVC was 987/3191 (30.9%) with an increasing trend from 28.8 to 33.2%. In the fourth period, out of 868 patients identified with IV indication, 288 had already been vaccinated (IVC?33.2%). After excluding patients presenting criteria of exclusion, IV was proposed to 475 patients: 317 (66.7%) accepted. The vaccination rate after patient’s acceptance was 89.6% (288/317). At the end of the EDVC, influenza vaccination coverage was 572 (284?+?288)/868 (65.9%). The delay between arrival at the ED and seeing the triage nurse and physician as well as the overall ED length of stay were not modified during the study period and before and during EDVC. EDVC effectively doubled the influenza vaccination coverage, without modifying ED time interval quality indicators. 相似文献
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You D Cochain C Loinard C Vilar J Mees B Duriez M Lévy BI Silvestre JS 《Hypertension》2008,51(6):1537-1544
We analyzed the effect of hypertension on postischemic vasculogenesis. Ischemia was induced by right femoral artery ligature in Wistar Kyoto rats (WKY) or spontaneously hypertensive rats (SHR) treated with or without angiotensin-converting enzyme inhibitor (Perindopril, 0.76 mg/kg/d) and angiotensin type 1 receptor blocker (losartan, 30 mg/kg/d). Basal postischemic neovascularization was reduced in SHR compared to WKY (P<0.05, n=8). Treatment with ACE inhibitor or angiotensin type 1 receptor blocker decreased blood pressure levels by 1.4- and 1.3-fold (P<0.001), respectively and restored vessel growth in SHR to WKY levels. Interestingly, 14 days after bone-marrow mononuclear cell (BM-MNC) transfusion, angiographic scores, capillary density, and foot perfusion were decreased by 1.4-, 1.5-, and 1.2-fold, respectively in SHR transfused with BM-MNCs isolated from SHR compared to those receiving BM-MNCs of WKY (P<0.05, n=6). Alteration in BM-MNCs proangiogenic potential was likely related to the reduction in their ability to mobilize into peripheral circulation, as revealed by the 2.9-fold decrease in number of circulating CD34+/CD117+ cells (P<0.001) and to differentiate into cells with endothelial phenotype, as revealed by the 2.1-fold reduction in percentages of DilLDL/BS-1 lectin positive cells (P<0.001). In addition, reactive oxygen species (ROS) levels were increased by 2.2-fold in SHR BM-MNCs compared to WKY BM-MNCs (P<0.01), as assessed by L-012 luminescence. Cotreatment with ACE inhibitor, angiotensin type 1 receptor blocker, or antioxidants (NAC 3 mmol/L, Apocynin 200 micromol/L) reduced ROS levels, improved the number of DilLDL/BS-1 lectin-positive cells by around 1.5-fold, and restored BM-MNCs proangiogenic effects in ischemic hindlimb. In conclusion, alteration in progenitor cell proangiogenic function may participate to the hypertension-induced impairment in postischemic revascularization. 相似文献
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100.
Bendall JK Damy T Ratajczak P Loyer X Monceau V Marty I Milliez P Robidel E Marotte F Samuel JL Heymes C 《Circulation》2004,110(16):2368-2375