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91.
Cara Nethercott Amanda N. Mabbett Makrina Totsika Paul Peters Juan C. Ortiz Graeme R. Nimmo Geoffrey W. Coombs Mark J. Walker Mark A. Schembri 《Journal of clinical microbiology》2013,51(7):2131-2138
Infective endocarditis (IE) is a life-threatening infection of the heart endothelium and valves. Staphylococcus aureus is a predominant cause of severe IE and is frequently associated with infections in health care settings and device-related infections. Multilocus sequence typing (MLST), spa typing, and virulence gene microarrays are frequently used to classify S. aureus clinical isolates. This study examined the utility of these typing tools to investigate S. aureus epidemiology associated with IE. Ninety-seven S. aureus isolates were collected from patients diagnosed with (i) IE, (ii) bloodstream infection related to medical devices, (iii) bloodstream infection not related to medical devices, and (iv) skin or soft-tissue infections. The MLST clonal complex (CC) for each isolate was determined and compared to the CCs of members of the S. aureus population by eBURST analysis. The spa type of all isolates was also determined. A null model was used to determine correlations of IE with CC and spa type. DNA microarray analysis was performed, and a permutational analysis of multivariate variance (PERMANOVA) and principal coordinates analysis were conducted to identify genotypic differences between IE and non-IE strains. CC12, CC20, and spa type t160 were significantly associated with IE S. aureus. A subset of virulence-associated genes and alleles, including genes encoding staphylococcal superantigen-like proteins, fibrinogen-binding protein, and a leukocidin subunit, also significantly correlated with IE isolates. MLST, spa typing, and microarray analysis are promising tools for monitoring S. aureus epidemiology associated with IE. Further research to determine a role for the S. aureus IE-associated virulence genes identified in this study is warranted. 相似文献
92.
Thomas Klopstock MD Aleksandar Videnovic MD Almut Turid Bischoff MD Cecilia Bonnet MD Laura Cif MD Cynthia Comella MD Marta Correa-Vela MD Maria L. Escolar MD Jamie L. Fraser MD Victoria Gonzalez MD Neal Hermanowicz MD Robert Jech MD Hyder A. Jinnah MD Tomasz Kmiec MD Anthony Lang MD Maria J. Martí MD Saadet Mercimek-Andrews MD Migvis Monduy MD Graeme A.M. Nimmo MBBS Belen Perez-Dueñas MD Helle Cecilie Viekilde Pfeiffer MD Lluis Planellas MD Emmanuel Roze MD Nivedita Thakur MD Laura Tochen MD Nora Vanegas-Arroyave MD Giovanna Zorzi MD Colleen Burns PhD Feriandas Greblikas MD 《Movement disorders》2021,36(6):1342-1352
93.
Edwards Richard Greenwood Hannah E. McRobbie Graeme Khan Imtiaz Witney Timothy H. 《Molecular imaging and biology》2021,23(6):854-864
Molecular Imaging and Biology - (S)-4-(3-18F-Fluoropropyl)-?-Glutamic Acid ([18F]FSPG) is a radiolabeled non-natural amino acid that is used for positron emission tomography (PET) imaging of... 相似文献
94.
95.
Does fetal growth restriction lead to increased brain injury as detected by neonatal cranial ultrasound in premature infants? 下载免费PDF全文
96.
Tihana Bicanic Christian Bottomley Angela Loyse Annemarie E. Brouwer Conrad Muzoora Kabanda Taseera Arthur Jackson Jacob Phulusa Mina C. Hosseinipour Charles van der Horst Direk Limmathurotsakul Nicholas J. White Douglas Wilson Robin Wood Graeme Meintjes Thomas S. Harrison Joseph N. Jarvis 《Antimicrobial agents and chemotherapy》2015,59(12):7224-7231
Amphotericin B deoxycholate (AmBd) is the recommended induction treatment for HIV-associated cryptococcal meningitis (CM). Its use is hampered by toxicities that include electrolyte abnormalities, nephrotoxicity, and anemia. Protocols to minimize toxicity are applied inconsistently. In a clinical trial cohort of AmBd-based CM induction treatment, a standardized protocol of preemptive hydration and electrolyte supplementation was applied. Changes in blood counts, electrolyte levels, and creatinine levels over 14 days were analyzed in relation to the AmBd dose, treatment duration (short course of 5 to 7 days or standard course of 14 days), addition of flucytosine (5FC), and outcome. In the 368 patients studied, the hemoglobin levels dropped by a mean of 1.5 g/dl (95% confidence interval [CI], 1.0 to 1.9 g/dl) following 7 days of AmBd and by a mean of 2.3 g/dl (95% CI, 1.1 to 3.6 g/dl) after 14 days. Serum creatinine levels increased by 37 μmol/liter (95% CI, 30 to 45 μmol/liter) by day 7 and by 49 μmol/liter (95% CI, 35 to 64μmol/liter) by day 14 of AmBd treatment. Overall, 33% of patients developed grade III/IV anemia, 5.6% developed grade III hypokalemia, 9.5% had creatinine levels that exceeded 220 μmol, and 6% discontinued AmBd prematurely. The addition of 5FC was associated with a slight increase in anemia but not neutropenia. Laboratory abnormalities stabilized or reversed during the second week in patients on short-course induction. Grade III/IV anemia (adjusted odds ratio [aOR], 2.2; 95% CI, 1.1 to 4.3; P = 0.028) and nephrotoxicity (aOR, 4.5; 95% CI, 1.8 to 11; P = 0.001) were risk factors for 10-week mortality. In summary, routine intravenous saline hydration and preemptive electrolyte replacement during AmBd-based induction regimens for HIV-associated CM minimized the incidence of hypokalemia and nephrotoxicity. Anemia remained a concerning adverse effect. The addition of flucytosine was not associated with increased neutropenia. Shorter AmBd courses were less toxic, with rapid reversibility. 相似文献
97.
98.
Weise M Drinkard B Mehlinger SL Holzer SM Eisenhofer G Charmandari E Chrousos GP Merke DP 《The Journal of clinical endocrinology and metabolism》2004,89(8):3679-3684
Classic congenital adrenal hyperplasia (CAH) is associated with impaired function of the adrenal cortex and medulla leading to decreased production of cortisol and epinephrine. As a result, the normal exercise-induced rise in blood glucose is markedly blunted in such individuals. We examined whether an extra dose of hydrocortisone, similar to that given during other forms of physical stress such as intercurrent illness, would normalize blood glucose levels during exercise in patients with CAH. We studied hormonal, metabolic, and cardiorespiratory parameters in response to a standardized high-intensity exercise protocol in nine adolescent patients with classic CAH. Patients were assigned to receive either an additional morning dose of hydrocortisone or placebo, in addition to their usual glucocorticoid and mineralocorticoid replacement in a randomized, double-blind, crossover design 1 h before exercising. Although plasma cortisol levels approximately doubled after administration of the additional hydrocortisone dose compared with the usual single dose, fasting and exercise-induced blood glucose levels did not differ. In addition, no differences were observed in the serum concentrations of the glucose-modulating hormones epinephrine, insulin, glucagon, and GH and of the metabolic parameters lactate and free fatty acids. Although maximal heart rate was slightly higher after stress dosing (193 +/- 3 vs. 191 +/- 3 beats/min, mean +/- sem, P < 0.05), this did not affect exercise performance or perceived exertion. We conclude that patients with classic CAH do not benefit from additional hydrocortisone during short-term, high-intensity exercise. Although this has not been tested with long-term exercise, a high degree of caution should be used when considering the frequent use of additional hydrocortisone administration with exercise, given the adverse side effects of glucocorticoid excess. 相似文献
99.
Eisenhofer G Bornstein SR Brouwers FM Cheung NK Dahia PL de Krijger RR Giordano TJ Greene LA Goldstein DS Lehnert H Manger WM Maris JM Neumann HP Pacak K Shulkin BL Smith DI Tischler AS Young WF 《Endocrine-related cancer》2004,11(3):423-436
Pheochromocytomas are rare catecholamine-producing neuroendocrine tumors that are usually benign, but which may also present as or develop into a malignancy. Predicting such behavior is notoriously difficult and there are currently no curative treatments for malignant tumors. This report follows from a workshop at the Banbury Conference Center, Cold Spring Harbor, New York, on the 16th-18th November 2003, held to review the state of science and to facilitate future progress in the diagnosis and treatment of malignant pheochromocytoma. The rarity of the tumor and the resulting fragmented nature of studies, typically involving small numbers of patients, represent limiting factors to the development of effective treatments and diagnostic or prognostic markers for malignant disease. Such development is being facilitated by the availability of new genomics-based tools, but for such approaches to succeed ultimately requires comprehensive clinical studies involving large numbers of patients, stringently collected clinical data and tumor samples, and interdisciplinary collaborations among multiple specialist centers. Nevertheless, the well-characterized hereditary basis and the unique functional nature of these neuroendocrine tumors provide a useful framework that offers advantages for establishing the pathways of tumorigenesis and malignancy. Such findings may have relevance for understanding the basis of other more common malignancies where similar frameworks are not available. As the relevant pathways leading to pheochromocytoma are established it should be possible to take advantage of the new generation of drugs being developed to target specific pathways in other malignancies. Again the success of this will require well-designed and coordinated multi-center studies. 相似文献
100.
Jane D. Collier Julian Sale Peter J. Friend Neville V. Jamieson Roy Y. Calne Graeme J.M. Alexander 《Journal of hepatology》1998,29(6):999-1003
Background/Aims: The antiphospholipid syndrome is characterised by arterial and venous thromboses affecting small and large vessels, together with the presence of lupus anticoagulant and anticardiolipin antibodies.Methods: We report two cases of the antiphospholipid syndrome following liver transplantation which resulted in hepatic vessel thrombosis and subsequent graft loss, and we discuss the value of anticoagulation in prevention of further thrombotic episodes. Identification of these cases prompted a retrospective analysis for the presence of IgG anticardiolipin antibody, the most useful laboratory marker of vascular thrombosis in the antiphospholipid syndrome. Serum taken at 2 to 4 weeks following transplantation (when thrombotic events might be anticipated) was analysed further in 132 patients undergoing liver transplantation.Results: Hepatic vessel thrombosis occurred in (16%) post transplantation. Anticardiolipin IgG was present in (8.8%) recipients who developed a hepatic vessel thrombosis following liver transplantation, compared to (6.3%) (p=0.59) in whom transplantation was not complicated by hepatic vessel thrombosis.Conclusions: The presence of IgG anticardiolipin antibody was uncommon in recipients following liver transplantation and was not associated with an increased risk of hepatic vessel thrombosis. In contrast, the antiphospholipid syndrome which is rare may result in hepatic artery occlusion and graft loss, and so prompt recognition of the clinical syndrome is critical. Although screening for the antibody is not warranted in liver transplant recipients, it is important to be aware of the syndrome as optimal management of such cases may prevent graft loss. 相似文献