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John R. de Almeida Gordon H. Guyatt Sachin Sud Joanne Dorion Michael D. Hill Michael R. Kolber Jane Lea Sylvia Loong Reg Balvinder K. Somogyi Brian D. Westerberg Chris White Joseph M. Chen Bell Palsy Working Group Canadian Society of Otolaryngology – Head Neck Surgery Canadian Neurological Sciences Federation 《CMAJ》2014,186(12):917-922
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Mingone CJ Gupte SA Quan S Abraham NG Wolin MS 《Experimental biology and medicine (Maywood, N.J.)》2003,228(5):535-539
Heme is a co-factor required for the stimulation of soluble guanylate cyclase (sGC) by nitric oxide (NO) and carbon monoxide, and sGC activation by these agents is inhibited by superoxide. Because heme promotes oxidant generation, we examined the influence of rat pulmonary microvascular endothelial cells (PMECs) with a stable human heme oxygenase-1 (HO-1) transfection and heme on oxidant generation and cGMP. Culture of PMEC with low serum heme decreased cGMP and the detection of peroxide with 10 microM 2',7'-dichlorofluorescin diacetate and increased HO-1 further decreased cGMP without altering the peroxide detection under these conditions. Under conditions where heme (30 microM) has been shown to stimulate cGMP production in PMECsby mechanisms involving NO and CO, heme increased the detection of peroxide in a PMEC-dependent manner and HO-1 transfection did not markedly alter the effects heme on peroxide detection. The addition of 1 microM catalase markedly inhibited the effects of heme on peroxide detection whereas increasing (0.1 mM ebselen) or decreasing (depleting glutathione with 7 mM diethylmaleate) rates of intracellular peroxide metabolism or inhibiting the biosynthesis of oxidants (with 10 microM diphenyliodonium or 0.1 mM nitro-L-arginine) had only modest effects. The detection of superoxide by 10 microM dihydroethidium from PMECs was not increased by exposure to heme. These actions of oxidant probes suggest that intracellular oxidants have a minimal influence on the response to heme. Thus, exposure of PMECs to heme causes a complex response involving an extracellular generation of peroxide-derived oxidant species, which do not appear to originate from increases in intracellular superoxide or peroxide. This enables heme and HO to regulate sGC through mechanisms involving NO and CO, which are normally inhibited by superoxide. 相似文献
86.
Kale S Yende S Kong L Perkins A Kellum JA Newman AB Vallejo AN Angus DC;GenIMS Investigators 《PloS one》2010,5(11):e13852
Objective
To determine whether inflammatory and hemostasis response in patients hospitalized for pneumonia varies by age and whether these differences explain higher mortality in the elderly.Methods
In an observational cohort of subjects with community-acquired pneumonia (CAP) recruited from emergency departments (ED) in 28 hospitals, we divided subjects into 5 age groups (<50, 51–64, 65–74, 75–84, and ≥85). We measured circulating levels of inflammatory (TNF, IL-6, and IL-10), hemostasis (D-dimer, Factor IX, thrombin-antithrombin complex, antithrombin and plasminogen-activator inhibitor-1), and cell-surface markers (TLR-2, TLR-4, and HLA-DR) during the first week of hospitalization and at discharge and compared 90-day mortality. We used logistic regression to compare odds ratios (OR) for 90-day mortality between age groups, adjusting for differences in pre-infection factors alone and then additionally adjusting for immune markers.Results
Of 2,183 subjects, 495, 444, 403, 583, and 258 subjects were <50, 51–64, 65–74, 75–84, and ≥85 years of age, respectively. Large age-related differences were observed in 90-day mortality (0.82% vs. 3.2% vs. 6.4% vs. 12.8% vs. 13.6%, p<0.01). No age-related differences in inflammatory and cell surface markers occurred during the first week. Older subjects had higher pro-coagulant markers on ED presentation and over first week (p≤0.03), but these differences were modest (1.0–1.7-fold differences). Odds of death for older adults changed minimally in models incorporating differences in hemostasis and inflammatory markers (for subjects ≥85 compared to those <50, OR = 4.36, when adjusted for pre-infection factors and OR = 3.49 when additionally adjusted for hemostasis markers). At discharge, despite clinical recovery as evidenced by normal vital signs in >85% subjects, older subjects had modestly increased hemostasis markers and IL-6 levels (p<0.01).Conclusions
Modest age-related increases in coagulation response occur during hospitalization for CAP; however these differences do not explain the large differences in mortality. Despite clinical recovery, immune resolution may be delayed in older adults at discharge. 相似文献87.
He Xin Maier Chelsea Chavan Sachin G. Zhao Chen-Chen Alagoz Yagiz Cazzonelli Christopher Ghannoum Oula Tissue David T. Chen Zhong-Hua 《Plant Growth Regulation》2021,95(1):1-17
Plant Growth Regulation - Greenhouse horticulture (protected cropping) is essential in meeting increasing global food demand under climate change scenarios by ensuring sustainability, efficiency,... 相似文献
88.
Muthiah Subramanian Sachin Yalagudri Daljeet Kaur Saggu Vickram Vignesh Rangaswamy Calambur Narasimhan 《Indian pacing and electrophysiology journal》2021,21(3):169-173
A 40 year old man with frequent PVCs with two different morphologies was referred for catheter ablation. Although initial mapping in the RVOT revealed fragmented potentials 20ms earlier than PVC2 onset with a good pace map score, ablation at this site was unsuccessful. Subsequent mapping in the LCC/NCC junction revealed that local ventricular activation preceded QRS onset by 30 and 28 ms for PVC1 and PVC2, respectively. Altering the pacing output at this site produced QRS morphologies similar to PVC1(low output,6mA) and PVC2(high output,15mA) with better pace map scores compared to RVOT. During high-output pacing, there was an increase in stim-QRS latency with decremental conduction. Ablation at this site was successful and suppressed both PVCs. 相似文献
89.
Pitre Nandan N. Moses J. B. Tzeng Edith Abramowitch Steven Velankar Sachin S. 《Biomechanics and modeling in mechanobiology》2023,22(3):1083-1094
Biomechanics and Modeling in Mechanobiology - Composites comprising crimped fibers of finite length embedded in a soft matrix have the potential to mimic the strain-hardening behavior of tissues... 相似文献
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