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991.
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   
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Fresh frozen plasma (FFP) is prepared in blood banks world-wide as a by-product of red blood cell concentrate preparation. Appropriate clinical use is for coagulation factor disorders where appropriate concentrates are unavailable and when multiple coagulation factor deficits occur such as in surgery. Viral safety depends on donor selection and screening; thus, there continues to be a small but defined risk of viral transmission comparable with that exhibited by whole blood. We have prepared a virus sterilized FFP (S/D-FFP) by treatment of FFP with 1% tri(n-butyl)phosphate (TNBP) and 1% Triton X-100 at 30 degrees C for 4 hours. Added reagents are removed by extraction with soybean oil and chromatography on insolubilized C18 resin. Treatment results in the rapid and complete inactivation of greater than or equal to 10(7.5) infectious doses (ID50) of vesicular stomatitis virus (VSV) and greater than or equal to 10(6.9) ID50 of sindbis virus (used as marker viruses), greater than or equal to 10(6.2) ID50 of human immunodeficiency virus (HIV), greater than or equal to 10(6) chimp infectious doses (CID50) of hepatitis B virus (HBV), and greater than or equal to 10(5) CID50 of hepatitis C virus (HCV). Immunization of rabbits with S/D-FFP and subsequent adsorption of elicited antibodies with untreated FFP confirmed the absence of neoimmungen formation. Coagulation factor content was comparable with that found in FFP. Based on these laboratory and animal studies, together with the extensive history of the successful use of S/D-treated coagulation factor concentrates, we conclude that replacement of FFP with S/D-FFP, prepared in a manufacturing facility, will result in improved virus safety and product uniformity with no loss of efficacy.  相似文献   
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Objective

To evaluate tumor responses in patients treated with anti-angiogenic agents for non-small cell lung cancer (NSCLC) by assessing intratumoral changes using a dual-energy CT (DECT) (based on Choi''s criteria) and to compare it to traditional Response Evaluation Criteria in Solid Tumors (RECIST) criteria.

Materials and Methods

Ten NSCLC patients treated with bevacizumab underwent DECT. Tumor responses to anti-angiogenic therapy were assessed and compared with the baseline CT results using both RECIST (size changes only) and Choi''s criteria (reflecting net tumor enhancement). Kappa statistics was used to evaluate agreements between tumor responses assessed by RECIST and Choi''s criteria.

Results

The weighted κ value for the comparison of tumor responses between the RECIST and Choi''s criteria was 0.72. Of 31 target lesions (21 solid nodules, 8 lymph nodes, and two ground-glass opacity nodules [GGNs]), five lesions (16%) showed discordant responses between RECIST and Choi''s criteria. Iodine-enhanced images allowed for a distinction between tumor enhancement and hemorrhagic response (detected in 14% [4 of 29, excluding GGNs] of target lesions on virtual nonenhanced images).

Conclusion

DECT may serve as a useful tool for response evaluation after anti-angiogenic treatment in NSCLC patients by providing information on the net enhancement of target lesions without obtaining non-enhanced images.  相似文献   
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