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11.
Caroline Van De Wauwer Arne P. Neyrinck Nele Geudens Filip R. Rega Geert M. Verleden Erik Verbeken Toni E. Lerut Dirk E.M. Van Raemdonck 《European journal of cardio-thoracic surgery》2007,31(6):1125-1133
Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm−5) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH2O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH2O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion. 相似文献
12.
Dr. Vera J.S. Van de Velde Ph.D. Dr. Achiel P. Van Peer Ph.D. Dr. Joseph J.P. Heykants Ph.D. Mr. Robert J.H. Woestenborghs Chem. Eng. Dr. Patricia Van Rooy M.D. Mr. Karel L. De Beule Dip. Hosp. Pharm. Dr. Geert F.M.J. Cauwenbergh Ph.D. 《Pharmacotherapy》1996,16(3):424-428
Study Objective . To compare the pharmacokinetics of a single 100-mg oral dose of itraconazole administered as 10 ml of a 10-mg/ml itraconazole solution in hydroxypropyl-β-cyclodextrin under fasting versus postprandial conditions. Design . Open-label, two-way, randomized, crossover study. Setting . Janssen Research Foundation, Belgium. Patients . Twelve healthy volunteers. Interventions . Blood samples were obtained for pharmacokinetic analyses immediately before dosing and at regular intervals up to 96 hours after each dose. Blood and urine samples were obtained for hematologic, biochemical, and urinary safety analyses at baseline and at the end of the study. Measurements and Main Results . The mean peak plasma concentrations of both itraconazole and its active metabolite hydroxy-itraconazole were significantly higher under fasting conditions than under postprandial conditions. The mean times to peak concentration for both the parent compound and its metabolite were significantly shorter under fasting than under nonfasting conditions. The mean areas under the curve (AUC0–∞ and AUC0–24 hrs) were also significantly higher under fasting than under postprandial conditions. Conclusions . Our findings suggest that the higher bioavailability of this new formulation of itraconazole may be of benefit in seriously ill patients who are not able to ingest adequate quantities of food. The fact that the solution was also well tolerated and was not associated with clinically significant changes in any laboratory value further underscores the potential utility of this dosing form. 相似文献
13.
In a previous study in conscious spontaneously hypertensive rats (SHR), we observed an immediate decrease in the cardiac index (CI) and an increase in the total peripheral resistance index (TPRI) following the administration of furosemide. The present study was designed to evaluate the regional hemodynamic effects and the involvement of sinoaortic baroreceptors in the increase in TPRI. In SHR instrumented for the measurement of central hemodynamics, 8 mg.kg-1 furosemide decreased CI from 31.0 +/- 2.5 ml.min-1.100 g bw-1 by 9.5 +/- 1.3 ml.min-1.100 g bw-1 (n = 7). TPRI increased maximally from 5.7 +/- 0.8 by 2.7 +/- 0.5 mm Hg.min.100 g bw.ml-1. The effect on TPRI was not affected by sinoaortic denervation (SAD) to abolish arterial baroreflexes. However, furosemide induced a significantly greater decrease in CI (-12.6 +/- 1.2 ml.min-1.100 g bw-1; n = 7) after SAD. Furosemide effectively reduced the mean arterial pressure in SAD SHR (-21 +/- 9 mm Hg) but not in sham-denervated SHR. Furosemide (8 mg.kg-1) reduced renal, mesenteric and hindquarter blood flow to a comparable extent (approximately 20%) in intact SHR. The reduction in renal flow at 3.5 min after injection (-17.9 +/- 4.1%; n = 8) was significantly greater than the reduction in mesenteric (-7.1 +/- 4.7%) and hindquarter blood flow (-4.2 +/- 3.7%), suggesting that the renal bed responds faster. Thereafter, the flow reductions in the three beds were not different. The results show that furosemide causes a general vasoconstriction in conscious SHR.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Smits PH Bakker R Jong E Mulder JW Meenhorst PL Kleter B van Doorn LJ Quint WG 《Journal of clinical microbiology》2005,43(12):5936-5939
Infection with human immunodeficiency virus (HIV) and the resulting immunosuppression are associated with an increased risk for human papillomavirus (HPV) persistence and related malignancies. In the present study we investigated the prevalence of HPV in urine samples from 104 HIV-infected men with low CD4+ cell counts (<100 per mm(3)) and 115 urine samples from HIV-negative men. A high prevalence of HPV DNA (39.4%) was found in the HIV patients. Most of the HPV types were high risk (81.4%), with HPV 52 as the most prevalent type (12.5%), followed by HPV 18 (6.7%), HPV 35 (5.8%), and HPV 70 (4.8%). Multiple HPV genotypes were observed in 17 (41%) of the 41 HPV- and HIV-positive men. In contrast, only 11 (9.6%) HPV DNA-positive cases were observed among the 115 HIV-uninfected men, and 3 (27.3%) contained multiple genotypes. Quantitative analyses indicated that the HPV viral load, as measured in urine samples, is significantly higher in HIV-positive men compared to HIV-negative men. In the present study we show that urine samples are useful for detecting HPV DNA, there is a high prevalence of HPV in HIV-positive men, and the HPV viral load is substantially higher in HIV-positive than in HIV-negative men. More studies are needed to evaluate the risk and natural development of HPV-related malignancies in HIV-positive men. 相似文献
18.
Pernelle A Smits Laurel S Kleppe Tyra A Witt Cheri S Mueske Richard G Vile Robert D Simari 《Endothelium》2007,14(1):1-5
Cells with an endothelial phenotype can be cultured from peripheral blood. These cells include cells of a monocytic origin with endothelial features (culture-modified mononuclear cells, CMMCs) and, at later time points, blood outgrowth endothelial cells (BOECs). Both are promising candidates for systemic cell-based cardiovascular therapies and each may have unique capabilities. Indeed, the combined use of both cell types has been shown to have synergistic therapeutic features requiring simultaneous delivery. However, the majority of preclinical studies of cell delivery have used splenectomized animals to increase systemic distribution. The goal of this study was to directly compare the distribution of these two cell types following systemic delivery in an intact animal model. A similar pattern of delivery was seen following delivery of both cell types with detection in the lung, liver, bone marrow, and spleen. Taken together, the data suggest that strategies using systemic delivery of circulation-derived cells must consider the distribution and efficiency of delivery in intact animals. 相似文献
19.
De Baere T Muylaert A Everaert E Wauters G Claeys G Verschraegen G Vaneechoutte M 《Journal of clinical microbiology》2002,40(7):2693-2695
A gram-negative alkaline phosphatase- and pyrrolidone peptidase-positive rod-shaped bacterium (CCUG 45702) was isolated from two aerobic blood cultures from a female cancer patient. No identification could be reached using phenotypic techniques. Amplification of the tRNA intergenic spacers revealed fragments with lengths of 116, 133, and 270 bp, but no such pattern was present in our reference library. Sequencing of the 16S rRNA gene revealed its identity as Moraxella atlantae, a species isolated only rarely and published only once as causing infection. In retrospect, the phenotypic characteristics fit the identification as M. atlantae (formerly known as CDC group M-3). Comparative 16S rRNA sequence analysis indicates that M. atlantae, M. lincolnii, and M. osloensis might constitute three separate genera within the MORAXELLACEAE: After treatment with amoxicillin-clavulanic acid for 2 days, fever subsided and the patient was dismissed. 相似文献
20.
In Vitro Expression of Adhesion Receptors and Diapedesis by Polymorphonuclear Neutrophils during Experimentally Induced Streptococcus uberis Mastitis
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Elke Smits Christian Burvenich Albert J. Guidry Eddy Roets 《Infection and immunity》1998,66(6):2529-2534
The expression of adhesion receptors and diapedesis by polymorphonuclear neutrophils (PMN) were studied before and during experimentally induced Streptococcus uberis mastitis. Both quarters of the left half of the udders of five midlactation cows were inoculated with a suspension containing approximately 500 CFU of S. uberis 0140J. Clinical signs of an inflammatory reaction and leukocyte influx were observed 24 h after challenge. The expression of CD11b/CD18 adhesion receptors, determined by flow cytometry, was upregulated 24 h after challenge. A confluent monolayer of bovine secretory mammary epithelial cells on collagen-coated inserts was used to study PMN diapedesis. Bovine C5a was used as the chemoattractant. An 80% decrease in PMN diapedesis was observed 24 h after challenge. The decrease in diapedesis continued for 3 weeks after challenge. 相似文献