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991.
Anaissie EJ Stratton SL Dignani MC Lee CK Summerbell RC Rex JH Monson TP Walsh TJ 《Blood》2003,101(7):2542-2546
The incidence of mold infections in patients with hematologic malignancies continues to increase despite the widespread use of air filtration systems, suggesting the presence of other hospital sources for these molds. Water sources are known to harbor pathogenic molds. We examined samples from water, water surfaces, air, and other environment sources from a bone marrow transplantation unit with optimal air precautions. Molds (Aspergillus species, others) were recovered in 70% of 398 water samples, in 22% of 1311 swabs from plumbing structures and environmental surfaces, and in 83% of 274 indoor air samples. Microscopic examination of the water plumbing lines revealed hyphal forms compatible with molds. Four findings suggest that indoor airborne molds were aerosolized from the water: (1) higher mean airborne concentrations of molds in bathrooms (16.1 colony-forming units [CFU]/m(3)) than in patient rooms (7 CFU/m(3)) and hallways (8.6 CFU/m(3); P =.00005); (2) a strong type and rank correlation between molds isolated from hospital water and those recovered from indoor hospital; (3) lack of seasonal correlation between the airborne mold concentration in outdoor and indoor air; and (4) molecular relatedness between a clinical strain and a water-related strain (previously reported). Hospital water distribution systems may serve as a potential indoor reservoir of Aspergillus and other molds leading to aerosolization of fungal spores and potential exposure for patients. 相似文献
992.
Ongoing right ventricular hemodynamics in heart failure: clinical value of measurements derived from an implantable monitoring system 总被引:3,自引:0,他引:3
Adamson PB Magalski A Braunschweig F Böhm M Reynolds D Steinhaus D Luby A Linde C Ryden L Cremers B Takle T Bennett T 《Journal of the American College of Cardiology》2003,41(4):565-571
OBJECTIVES: This study examined the characteristics of continuously measured right ventricular (RV) hemodynamic information derived from an implantable hemodynamic monitor (IHM) in heart failure patients. BACKGROUND: Hemodynamic monitoring might improve the day-to-day management of patients with chronic heart failure (CHF). Little is known about the characteristics of long-term hemodynamic information in patients with CHF or how such information relates to meaningful clinical events. METHODS: Thirty-two patients with CHF received a permanent RV IHM system similar to a single-lead pacemaker. Right ventricular systolic and diastolic pressures, heart rate, and pressure derivatives were continuously measured for nine months without using the data for clinical decision-making or management of patients. Data were then made available to clinical providers, and the patients were followed up for 17 months. Pressure characteristics during optimal volume, clinically determined volume-overload exacerbations, and volume depletion events were examined. The effect of IHM on hospitalizations was examined using the patients' historical controls. RESULTS: Long-term RV pressure measurements had either marked variability or minimal time-related changes. During 36 volume-overload events, RV systolic pressures increased by 25 +/- 4% (p < 0.05) and heart rate increased by 11 +/- 2% (p < 0.05). Pressure increases occurred in 9 of 12 events 4 +/- 2 days before the exacerbations requiring hospitalization. Hospitalizations before using IHM data for clinical management averaged 1.08 per patient year and decreased to 0.47 per patient-year (57% reduction, p < 0.01) after hemodynamic data were used. CONCLUSIONS: Long-term ambulatory pressure measurements from an IHM may be helpful in guiding day-to-day clinical management, with a potentially favorable impact on CHF hospitalizations. 相似文献
993.
Cecilia A. Muller Lionel H. Opie Carlos A. Pineda Joy McCarthy Vladimir Kraljevic 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1998,12(5):449-455
The combination of a calcium antagonist with an angiotensin-converting enzyme (ACE) inhibitor is increasingly used in the therapy of hypertension, but there are no experimental data supporting the use of this combination in acute myocardial ischemia and reperfusion. We tested the effects of oral pretreatment in a pig model, paying special attention to arrhythmias and adverse hemodynamic effects. Pigs received verapamil 240 mg + trandolapril 4 mg, verapamil 240 mg, or placebo orally once daily for 10 days, after which a coronary artery was ligated for 20 minutes and then allowed to reperfuse. The ventricular fibrillation threshold (VFT) was measured during ischemia to assess the vulnerability of the heart to ventricular fibrillation, whereas spontaneous tachyarrhythmias were monitored during reperfusion. Regional left ventricular (LV) blood flow was measured with radioactive microspheres. During the ischemic period, both the combination of verapamil plus trandolapril, and verapamil alone, prevented a fall in the VFT, indicating antiarrhythmic activity. The combination maintained LV contractile activity and cardiac output (CO) at preligation levels, whereas verapamil alone decreased cardiac output. During reperfusion, verapamil plus trandolapril prevented spontaneous ventricular tachyarrhythmias and increased blood flow in the reperfused zone. In contrast, verapamil was not antiarrhythmic and decreased CO. Thus the addition of the ACE inhibitor trandolapril to the calcium antagonist verapamil resulted in antiarrhythmic activity during ischemia and reperfusion, and produced a better hemodynamic profile. 相似文献
994.
Gregory V. Schimizzi Linda X. Jin Jesse T. Davidson Bradley A. Krasnick Cecilia G. Ethun Timothy M. Pawlik George Poultsides Thuy Tran Kamran Idrees Chelsea A. Isom Sharon M. Weber Ahmed Salem William G. Hawkins Steven M. Strasberg Maria B. Doyle William C. Chapman Robert C.G. Martin Charles Scoggins Ryan C. Fields 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2018,20(4):332-339
Background
Surgical resection is the cornerstone of curative-intent therapy for patients with hilar cholangiocarcinoma (HC). The role of vascular resection (VR) in the treatment of HC in western centres is not well defined.Methods
Utilizing data from the U.S. Extrahepatic Biliary Malignancy Consortium, patients were grouped into those who underwent resection for HC based on VR status: no VR, portal vein resection (PVR), or hepatic artery resection (HAR). Perioperative and long-term survival outcomes were analyzed.Results
Between 1998 and 2015, 201 patients underwent resection for HC, of which 31 (15%) underwent VR: 19 patients (9%) underwent PVR alone and 12 patients (6%) underwent HAR either with (n = 2) or without PVR (n = 10). Patients selected for VR tended to be younger with higher stage disease. Rates of postoperative complications and 30-day mortality were similar when stratified by vascular resection status. On multivariate analysis, receipt of PVR or HAR did not significantly affect OS or RFS.Conclusion
In a modern, multi-institutional cohort of patients undergoing curative-intent resection for HC, VR appears to be a safe procedure in a highly selected subset, although long-term survival outcomes appear equivalent. VR should be considered only in select patients based on tumor and patient characteristics. 相似文献995.
Haemophilus influenzae from patients with chronic obstructive pulmonary disease exacerbation induce more inflammation than colonizers 总被引:3,自引:0,他引:3
Chin CL Manzel LJ Lehman EE Humlicek AL Shi L Starner TD Denning GM Murphy TF Sethi S Look DC 《American journal of respiratory and critical care medicine》2005,172(1):85-91
RATIONALE: Airway infection with Haemophilus influenzae causes airway inflammation, and isolation of new strains of this bacteria is associated with increased risk of exacerbations in patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE: To determine whether strains of H. influenzae associated with exacerbations cause more inflammation than strains that colonize the airways of patients with COPD. METHODS: Exacerbation strains of H. influenzae were isolated from patients during exacerbation of clinical symptoms with subsequent development of a homologous serum antibody response and were compared with colonization strains that were not associated with symptom worsening or an antibody response. Bacterial strains were compared using an in vivo mouse model of airway infection and in vitro cell culture model of bacterial adherence and defense gene and signaling pathway activation in primary human airway epithelial cells. RESULTS: H. influenzae associated with exacerbations caused more airway neutrophil recruitment compared with colonization strains in the mouse model of airway bacterial infection. Furthermore, exacerbation strains adhered to epithelial cells in significantly higher numbers and induced more interleukin-8 release after interaction with airway epithelial cells. This effect was likely mediated by increased activation of the nuclear factor-kappaB and p38 mitogen-activated protein kinase signaling pathways. CONCLUSIONS: The results indicate that H. influenzae strains isolated from patients during COPD exacerbations often induce more airway inflammation and likely have differences in virulence compared with colonizing strains. These findings support the concept that bacteria infecting the airway during COPD exacerbations mediate increased airway inflammation and contribute to decreased airway function. 相似文献
996.
Becattini Cecilia; Agnelli Giancarlo; Prandoni Paolo; Silingardi Mauro; Salvi Rosamaria; Taliani Maria Rita; Poggio Renzo; Imberti Davide; Ageno Walter; Pogliani Enrico; Porro Ferdinando; Casazza Franco 《European heart journal》2005,26(1):77-83
Aims To evaluate the incidence of cardiovascular events in thelong-term clinical course of patients with a first episode ofsymptomatic, objectively confirmed pulmonary embolism. Methods and results Three hundred and sixty patients with afirst episode of pulmonary embolism were included in a prospectivestudy: 209 with idiopathic pulmonary embolism and 151 with pulmonaryembolism associated with transient risk factors. The study outcomeswere cardiovascular events (recurrent venous thrombo-embolism,acute myocardial infarction, stroke, sudden otherwise unexplaineddeath), cardiovascular death, and death due to any cause. Themedian follow-up was 38 months. Sixty-four patients had at leastone cardiovascular event (5.5% patient-year). Recurrent venousthrombo-embolism occurred in 45 patients (3.9% patient-year),acute myocardial infarction in 12 patients (1.0% patient-year),stroke in six patients (0.5% patient-year), and sudden otherwiseunexplained death in four patients (0.3% patient-year). A cardiovascularevent occurred in 47 patients with idiopathic pulmonary embolism(7.5% patient-year) and in 17 patients with pulmonary embolismassociated with transient risk factors (3.1% patient-year) (RR2.0; 95% CI 1.203.34; P=0.006). Twenty patients withidiopathic pulmonary embolism (3.2% patient-year) and two patientswith pulmonary embolism associated with transient risk factors(0.4% patient-year) presented an arterial cardiovascular event(RR 7.2; 95% CI 1.7130.45; P=0.001). Thirty-three patientsdied (9.2%). Cardiovascular mortality and cancer mortality accountedfor 42.4 and 21.2% of overall mortality, respectively. Idiopathicpulmonary embolism was an independent predictor of cardiovascularevents after adjusting for age. Conclusions Cardiovascular events are more common in patientswith idiopathic pulmonary embolism than in patients with pulmonaryembolism associated with transient risk factors. Cardiovascularevents are the major cause of death in patients with idiopathicpulmonary embolism. 相似文献
997.
998.
Jong-Ryool Oh Harshad Kulkarni Cecilia Carreras Georg Schalch Jung-Joon Min Richard P. Baum 《Nuclear Medicine and Molecular Imaging》2012,46(2):129-133
Von Hippel-Lindau (VHL) disease is a dominantly inherited familial cancer syndrome with a variety of benign and malignant tumors such as retinal and central nervous system hemangioblastomas, endolymphatic sac tumors, renal cysts and tumors, pancreatic cysts and tumors, pheochromocytomas, and epididymal cystadenomas. Cross-sectional modalities (computed tomography and magnetic resonance imaging) as well as ultrasound play a major role in the initial evaluation and follow-up of the various manifestations of VHL disease. Ga-68-labeled somatostatin receptor analogs already have a significant role in the diagnosis, staging, and therapy management of neuroendocrine neoplasms and neural crest tumors. Herein, we report a case presenting a variety of malignancies in VHL and showing the usefulness of Ga-68 somatostatin receptor PET/CT as a one-stop-shop imaging modality in the management of VHL disease. 相似文献
999.
1000.