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Perflubron dosing affects ventilator-induced lung injury in rats with previous lung injury 总被引:1,自引:0,他引:1
OBJECTIVES: Randomized controlled trials of partial liquid ventilation in acute respiratory distress syndrome have been negative. Reasons for this failure may reside in the use of too large doses of perfluorocarbon. The objective was to evaluate whether various doses of perflubron affect ventilation-induced injury in edematous lungs in different ways. DESIGN: Prospective, controlled animal study. SETTING: Research laboratory of a university. SUBJECTS: Male Wistar rats weighing 300+/-20 g. INTERVENTIONS: Separate groups of rats were injected with alpha-naphtylthiourea to produce mild permeability pulmonary edema. They were then given 0, 7 (low), 13 (moderate), or 20 mL/kg (near functional residual capacity) perflubron doses and mechanically ventilated with a large (33 mL/kg) tidal volume for 15 mins. MEASUREMENTS AND MAIN RESULTS: 125I-albumin distribution space was used to assess lung microvascular permeability. Quasi-static respiratory system pressure-volume curves were analyzed. Administration of low and moderate perflubron doses significantly improved respiratory mechanics and reduced the ventilator-induced permeability alterations to the level observed in rats that were not ventilated. By contrast, a perflubron dose that was near functional residual capacity increased end-inspiratory plateau pressure and aggravated the permeability alterations due to high tidal volume ventilation. CONCLUSIONS: Near functional residual capacity but not low perflubron dose worsens ventilation-induced lung injury of preinjured lungs. This may provide some explanation for the negative results of the recent clinical trials, and it stresses the importance of the amount of perflubron used for partial liquid ventilation. 相似文献
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Kim D Harrison Beverly D Hiebert Arash Panahifar Janna M Andronowski Amir M Ashique Gavin A King Terra Arnason Kurtis J Swekla Peter Pivonka David ML Cooper 《Journal of bone and mineral research》2020,35(11):2211-2228
Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1–34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).. 相似文献
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Abstract: The study of plasma integrates physics, chemistry, biology, and engineering, and has recently engaged medicine and dental hygiene in research efforts. The study of plasma holds promise for a myriad of applications ranging from lasers and electronics, hazardous waste management, decontamination, sterilization and disinfection of foods, soil, water, instruments, to medical uses in wound healing and treating certain types of tumours and cancers. Plasma represents a new state-of-the-art sterilization and disinfection treatment for certain oral and enviornmental pathogens, heat-sensitive materials, contaminated medical waste, hard and soft surfaces, and ventilation systems may assist health care facilities in the management of various health concerns. The role that Low Temperature Atmospheric Pressure Plasma (LTAPP) could play in the inactivation of pathogenic microorganisms might prove to be a new, faster, noncorrosive, more economical alternative, as well as support green healthcare. 相似文献
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Neisser Deusch Weigert Kobrak Eckstein Rosenow Tobler Oppenheimer Holzer Finkenrath Dessecker A. W. Fischer Zuntz Peiper Simon Hoffa Eisner-Behrend Seligmann Braun Zinn Dietlen Levinger Kaufmann Reiss Schlesinger Hayward Desseker Eisner H. Hirschfeld Griesbach Dreyfuss Heinrich Davidsohn Freudenberg Jonas V. Jaschke Dietrich Teleky Schönberg 《Journal of molecular medicine (Berlin, Germany)》1922,1(18):910-917
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Ho Yu Cheng Sek Ying Chair Qun Wang Janet WH Sit Eliza ML Wong Siu Wai Tang 《老年心脏病学杂志》2016,13(5):415-419
Background Heart failure (HF) is a physically and socially debilitating disease that carries the burden of hospital re-admission and mortality. As an aging society, Hong Kong urgently needs to find ways to reduce the hospital readmission of HF patients. This study evaluates the effects of a nurse-led HF clinic on the hospital readmission and mortality rates among older HF patients in Hong Kong. Methods This study is a retrospective data analysis that compares HF patient in a nurse-led HF clinic in Hong Kong compared with HF patients who did not attend the clinic. The nurses of this clinic provide education on lifestyle modification and symptom monitoring, as well as titrate the medications and measure biochemical markers by following established protocols. This analysis used the socio-demographic and clinical data of HF patients who were aged ≥ 65 years old and stayed in the clinic over a six-month period. Results The data of a total of 78 HF patients were included in this data analysis. The mean age of the patients was 77.38 ± 6.80 years. Approximately half of the HF patients were male (51.3%), almost half were smokers (46.2%), and the majority received ≤ six years of formal education. Most of the HF patients (87.2%) belonged to classes II and III of the New York Heart Association Functional Classification, with a mean ejection fraction of 47.15 ± 20.31 mL. The HF patients who attended the clinic (n = 38, 75.13 ± 5.89 yrs) were significantly younger than those who did not attend the clinic (n = 40, 79.53 ± 6.96 yrs) (P = 0.04), and had lower recorded blood pressure. No other statistically significant difference existed between the socio-demographic and clinical characteristics of the two groups. The HF patients who did not attend the nurse-led HF clinic demonstrated a significantly higher risk of hospital readmission [odd ratio (OR): 7.40; P < 0.01] than those who attended after adjusting for the effect of age and blood pressure. In addition, HF patients who attended the clinic had lower mortality (n = 4) than those who did not attend (n = 14). However, such a difference did not reach statistical significance when the effects of age and blood pressure were adjusted. A significant reduction in systolic blood pressure [F (2, 94) = 3.39, P = 0.04] and diastolic blood pressure [F (2, 94) = 8.48, P < 0.01] was observed among the HF patients who attended the clinic during the six-month period. Conclusions The finding of this study suggests the important role of nurse-led HF clinics in reducing healthcare burden and improving patient outcomes among HF patients in Hong Kong. 相似文献