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41.
Sandrine Marquet Ianina Conte Belco Poudiougou Laurent Argiro Sandrine Cabantous Hélia Dessein Florence Burté Aboubacar A. Oumar Biobele J. Brown Abdoualye Traore Nathaniel K. Afolabi Abdoulaye Barry Samuel Omokhodion Ursule Ewanda Ndoumbe Wuraola A. Shokunbi Olugbemiro Sodeinde Ogobara Doumbo Delmiro Fernandez-Reyes Alain J. Dessein 《Infection and immunity》2016,84(2):590-597
Cerebral malaria (CM) is a neurological complication of infection with Plasmodium falciparum that is partly caused by cytokine-mediated inflammation. It is not known whether interleukin-17 (IL-17) cytokines, which regulate inflammation, control the development of CM. To evaluate the involvement of IL-17 cytokines in CM, we analyzed 46 common polymorphisms in IL17A, IL17F, and IL17RA (which encodes the common receptor chain of the members of the IL-17 family) in two independent African populations. A case-control study involving 115 Nigerian children with CM and 160 controls from the community (CC) showed that IL17F reference single nucleotide polymorphism (SNP) 6913472 (rs6913472) (P = 0.004; odds ratio [OR] = 3.12), IL17F rs4715291 (P = 0.004; OR = 2.82), IL17RA rs12159217 (P = 0.01; OR = 2.27), and IL17RA rs41396547 (P = 0.026; OR = 3.15) were independently associated with CM. A replication study was performed in 240 nuclear Malian family trios (two parents with one CM child). We replicated the association for 3 SNPs, IL17F rs6913472 (P = 0.03; OR = 1.39), IL17RA rs12159217 (P = 0.01; OR = 1.52), and IL17RA rs41396547 (P = 0.04; OR = 3.50). We also found that one additional SNP, IL17RA rs41433045, in linkage disequilibrium (LD) with rs41396547, was associated with CM in both Nigeria and Mali (P = 0.002; OR = 4.12 in the combined sample). We excluded the possibility that SNPs outside IL17F and IL17RA, in strong LD with the associated SNPs, could account for the observed associations. Furthermore, the results of a functional study indicated that the aggravating GA genotype of IL17F rs6913472 was associated with lower IL-17F concentrations. Our findings show for the first time that IL17F and IL17RA polymorphisms modulate susceptibility to CM and provide evidence that IL-17F protects against CM. 相似文献
42.
Barasch E Fan D Chukwu EO Han J Passick M Petillo F Norales A Reichek N 《The Journal of heart valve disease》2008,17(1):81-88
BACKGROUND AND AIM OF THE STUDY: A significant proportion of patients with severe valvular aortic stenosis (AS) and preserved left ventricular (LV) systolic function have low transvalvular gradients. The study aim was to determine the mechanisms and outcome of patients with this hemodynamic profile of AS. METHODS: Among 1,679 patients who underwent transthoracic echocardiography for the evaluation of AS at the authors' institution, 215 (105 females, 110 males; mean age: 77 +/- 10 years) had isolated AS (mean aortic valve area index 0.39 +/- 0.1 cm2/m2), normal sinus rhythm and normal LV ejection fraction. The mean follow up was 23 +/- 12 months, and the end-points were mortality, aortic valve replacement (AVR), or mortality or AVR. RESULTS: Forty-seven patients had a transvalvular mean gradient (MG) <30 mmHg (MG(low)) and 168 had MG > or = 30 mmHg (MG(high)). Compared to MG(high), the MG(low) group had a higher prevalence of hypertension, lower LV end-diastolic volume index (47 +/- 9 versus 56 +/- 12 ml/m2, p <0.0001), lower LV stroke vol-ume index (37 +/- 12 versus 41 +/- 11 ml/beat, p <0.0002), a lesser severity of stenosis (aortic valve area index 0.37 +/- 0.09 versus 0.46 +/- 0.09 cm2/m2, p <0.0001) and a higher systemic vascular resistance (2163 +/- 754 versus 1879 +/- 528 dyne cm s(-5). The LV end-diastolic volume index, systemic vascular resistance and energy loss index were predictors of MG <30 mmHg (OR = 0.30, 95% CI, 0.12, 0.62; OR = 3.05, 95% CI, 1.71, 6.26; and OR = 6.76, 95% CI, 3.44,15.38, respectively). MG <30 mmHg (MGhigh) was associated with almost 50% lower referral to surgery and a two-fold increase in preoperative mortality. CONCLUSION: In severe AS with a normal LV ejection fraction, MG <30 mmHg is related to a lesser severity of stenosis, a smaller LV volume, a lower flow rate and a higher systemic vascular resistance. Compared to the MG(high) group, these patients were less frequently referred to surgery and had a higher mortality. 相似文献
43.
Vishal Kapur MD Nathaniel R. Smilowitz MD Giora Weisz MD 《Catheterization and cardiovascular interventions》2014,83(6):915-921
A remote‐controlled, robotic system was developed to address procedural challenges and occupational hazards associated with traditional percutaneous coronary intervention (PCI). The PRECISE (Percutaneous Robotically Enhanced Coronary Intervention) Study demonstrated the safety and feasibility of the robotic system. We report four cases of complex coronary interventions demonstrating the capabilities of robotic‐enhanced PCI to treat multilesion, multivessel coronary disease, saphenous venous graft disease, and an ST‐elevation myocardial infarction. The robotic system offers enhanced visibility, precise measurement, accurate stent positioning, improved ergonomics, and superior operator protection from radiation. © 2013 Wiley Periodicals, Inc. 相似文献
44.
Alison E. Murray Fabien Kenig Christian H. Fritsen Christopher P. McKay Kaelin M. Cawley Ross Edwards Emanuele Kuhn Diane M. McKnight Nathaniel E. Ostrom Vivian Peng Adrian Ponce John C. Priscu Vladimir Samarkin Ashley T. Townsend Protima Wagh Seth A. Young Pung To Yung Peter T. Doran 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(50):20626-20631
The permanent ice cover of Lake Vida (Antarctica) encapsulates an extreme cryogenic brine ecosystem (−13 °C; salinity, 200). This aphotic ecosystem is anoxic and consists of a slightly acidic (pH 6.2) sodium chloride-dominated brine. Expeditions in 2005 and 2010 were conducted to investigate the biogeochemistry of Lake Vida’s brine system. A phylogenetically diverse and metabolically active Bacteria dominated microbial assemblage was observed in the brine. These bacteria live under very high levels of reduced metals, ammonia, molecular hydrogen (H2), and dissolved organic carbon, as well as high concentrations of oxidized species of nitrogen (i.e., supersaturated nitrous oxide and ∼1 mmol⋅L−1 nitrate) and sulfur (as sulfate). The existence of this system, with active biota, and a suite of reduced as well as oxidized compounds, is unusual given the millennial scale of its isolation from external sources of energy. The geochemistry of the brine suggests that abiotic brine-rock reactions may occur in this system and that the rich sources of dissolved electron acceptors prevent sulfate reduction and methanogenesis from being energetically favorable. The discovery of this ecosystem and the in situ biotic and abiotic processes occurring at low temperature provides a tractable system to study habitability of isolated terrestrial cryoenvironments (e.g., permafrost cryopegs and subglacial ecosystems), and is a potential analog for habitats on other icy worlds where water-rock reactions may cooccur with saline deposits and subsurface oceans. 相似文献
45.
Masateru Takigawa Jatin Relan Ruairidh Martin Steven Kim Takeshi Kitamura Antonio Frontera Ghassen Cheniti Konstantinos Vlachos Grégoire Massoullié Claire A. Martin Nathaniel Thompson Michael Wolf Felix Bourier Anna Lam Josselin Duchateau Nicolas Klotz Thomas Pambrun Arnaud Denis Pierre Jaïs 《Heart rhythm》2018,15(12):1853-1861
46.
47.
Akiyama Shintaro Cohen Nathaniel A. Steinberg Joshua M. Friedberg Scott Cohen Russell D. 《Digestive diseases and sciences》2022,67(3):805-809
Digestive Diseases and Sciences - 相似文献
48.
Individuals with diabetes mellitus have cardiovascular disease (CVD) mortality comparable to nondiabetics who have suffered
a myocardial infarction or stroke. Aggressive management of risk factors such as hypertension, dyslipidemia, and platelet
dysfunction in persons with diabetes has been shown to reduce morbidity and mortality in prospective randomized controlled
clinical trials. Accordingly, there are national mandates to lower blood pressure to less than 130/85 mm Hg, reduce low-density
lipoprotein cholesterol to less than 100 mg/dL, and institute aspirin therapy in adult patients with diabetes. Although not
definitively shown to reduce CVD, there are also recommendations to control the level of glycemia, as well. This article discusses
CVD risk factors in the diabetic patient with hypertension. 相似文献
49.
Giulio Innamorati Hamid M. Sadeghi Nathaniel T. Tran Mariel Birnbaumer 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(5):2222-2226
Receptor recycling plays a critical role in the regulation of cellular responsiveness to environmental stimuli. Agonist-promoted phosphorylation of G protein-coupled receptors has been related to their desensitization, internalization, and sequestration. Dephosphorylation of internalized G protein-coupled receptors by cytoplasmic phosphatases has been shown to be pH-dependent, and it has been postulated to be necessary for receptors to recycle to the cell surface. The internalized V2 vasopressin receptor (V2R) expressed in HEK 293 cells is an exception to this hypothesis because it does not recycle to the plasma membrane for hours after removal of the ligand. Because this receptor is phosphorylated only by G protein-coupled receptor kinases (GRKs), the relationship between recycling and GRK-mediated phosphorylation was examined. A nonphosphorylated V2R, truncated upstream of the GRK phosphorylation sites, rapidly returned to the cell surface after removal of vasopressin. Less-drastic truncations of V2R revealed the presence of multiple phosphorylation sites and suggested a key role for a serine cluster present at the C terminus. Replacement of any one of Ser-362, Ser-363, or Ser-364 with Ala allowed quantitative recycling of full-length V2R without affecting the extent of internalization. Examination of the stability of phosphate groups incorporated into the recycling S363A mutant V2Rs revealed that the recycling receptor was dephosphorylated after hormone withdrawal, whereas the wild-type V2R was not, providing molecular evidence for the hypothesis that GRK sites must be dephosphorylated prior to receptor recycling. These experiments uncovered a role for GRK phosphorylation in intracellular sorting and revealed a GRK-dependent anchoring domain that blocks V2R recycling. 相似文献
50.