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CONTEXT: The hypothalamic-pituitary-adrenal axis is a major determinant of the host response to stress. The relationship between its activation and patient outcome is not known. OBJECTIVE: To evaluate the prognostic value of cortisol levels and a short corticotropin stimulation test in patients with septic shock. DESIGN AND SETTING: Prospective inception cohort study conducted between October 1991 and September 1995 in 2 teaching hospital adult intensive care units in France. PARTICIPANTS: A total of 189 consecutive patients who met clinical criteria for septic shock. INTERVENTION: A short corticotropin stimulation test was performed in all patients by intravenously injecting 0.25 mg of tetracosactrin; blood samples were taken immediately before the test (T0) and 30 (T30) and 60 (T60) minutes afterward. MAIN OUTCOME MEASURES: Twenty-eight-day mortality as a function of variables collected at the onset of septic shock, including cortisol levels before the corticotropin test and the cortisol response to corticotropin (delta max, defined as the difference between T0 and the highest value between T30 and T60). RESULTS: The 28-day mortality was 58% (95% confidence interval [CI], 51%-65%) and median time to death was 17 days (95% CI, 14-27 days). In multivariate analysis, independent predictors of death (P < or = .001 for all) were McCabe score greater than 0, organ system failure score greater than 2, arterial lactate level greater than 2.8 mmol/L, ratio of PaO2 to fraction of inspired oxygen no more than 160 mm Hg, cortisol level at T0 greater than 34 microg/dL and delta max no more than 9 microg/dL. Three groups of patient prognoses were identified: good (cortisol level at T0 < or = 34 microg/dL and delta max > 9 microg/dL; 28-day mortality rate, 26%), intermediate (cortisol level at T0 34 microg/dL and delta max < or = 9 microg/dL or cortisol level at T0 > 34 microg/dL and delta max > 9 microg/dL; 28-day mortality rate, 67%), and poor (cortisol level at T0 > 34 microg/dL and delta max < or = 9 microg/dL; 28-day mortality rate, 82%). CONCLUSION: Our data suggest that a short corticotropin test has a good prognostic value and could be helpful in identifying patients with septic shock at high risk for death.  相似文献   
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In this report we present in detail a non-invasive pulmonary application method that can be a useful tool in studying drug and vaccine delivery to the lower airways. In this method the formulation is sprayed directly into the lungs of mice via the endotracheal route using a MicroSprayer aerolizer. Mean droplet size produced was 8 microm, appropriate for deposition in the large airways. Endotracheal application of suspension of fluorescent nanospheres, 200 nm in size, by this method resulted in nanoparticle deposition in the smaller airways (bronchi and bronchioles). Mice showed full recovery one day after administration of 50 microl of formulation. Furthermore, no mortality was observed as a result of the technique. We conclude that this endotracheal application is a useful tool for studying pulmonary drug delivery in mice. The technique is especially useful for the pulmonary application of vaccines, since it enables multiple administrations without a need for analgesics.  相似文献   
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OBJECTIVES: To use 3-dimensional ultrasonography (3D-US) to determine the frequency of post-voiding residual volume (PVRV) > or =100 mL in primiparae 3 days after receiving epidural anesthesia for vaginal delivery. Potential relationships between day-3 PVRV > or =100 mL and obstetrical-pediatric parameters, especially those possibly implicated in post-obstetrical bladder dysfunction, were examined. STUDY DESIGN: We recruited 154 primiparae who vaginally delivered term singletons following uncomplicated pregnancies in the maternity unit of a French teaching hospital. All women had been systematically catheterized 2-h postpartum to measure precisely the volume of urine retained. On the morning of discharge (day 3), when the patient felt the urge to urinate, her 3D-US pre-voiding bladder volume was determined with BladderScan (BVI-3000), then her spontaneously voided urine was collected to accurately quantify its volume and 3D-US was repeated immediately to evaluate the PVRV. PVRV > or =100 mL on day 3 was considered pathological. RESULT: Among these 154 women, 88 (57%) felt the need to urinate and 97 (63%) had a retained volume > or =500 mL at 2-h postpartum. On day-3 postpartum, the median [range] volumes for the entire cohort were: 426.7 [158-999.7] mL 3D-US-measured pre-voiding, 350 [15-1000] mL collected by spontaneous urination, 82.2 [5.3-433.3] mL 3D-US-determined post-voiding; PVRV exceeded 100 mL for 55 (36%). According to our univariate analysis, no factor considered was able to predict PVRV > or =100 mL on day 3. CONCLUSION: Our observations confirmed the existence of PVRV > or =100 mL on day 3 in more than one-third of these primiparae who delivered vaginally under epidural anesthesia. No obstetrical-pediatric factor could be implicated in this bladder dysfunction. Therefore, we recommend frequent and systematic non-invasive 3D-US monitoring of all postpartum patients at least until day 3 to avoid excessive urine retention.  相似文献   
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PURPOSE: To compare the effects of recombinant activated factor VII (rFVIIa) and platelet-rich plasma (PRP) in an experimental model of bleeding and arterial thrombosis. METHODS: The Folts model was used in 60 rabbits. After anesthesia, the carotid artery was exposed and a 75% stenosis was induced. A compression injury of the artery triggered a series of cyclic flow reductions (CFRs). After counting baseline CFRs, animals were assigned randomly to one of four groups (n = 15 in each): control, PRP, rFVIIa and placebo. Control animals received 10 mL.kg(-1) of saline while 10 mL.kg(-1) of a hydroxyethyl starch solution (200,000/6%/0.5) were infused in the three other groups. CFRs were measured again, followed by treatment with PRP, rFVIIa or placebo and by a final measurement of CFRs. At the end of each observation period, an ear immersion bleeding time (BT) was measured and a blood sample was drawn for the evaluation of hematological variables. Microvascular bleeding was evaluated at the end of the experiment in grams of blood shed from liver and spleen sections. Results are presented as median (range). RESULTS: rFVIIa shortened the BT and decreased microvascular bleeding as compared with placebo [60 (35-100) sec vs 110 (50-140) sec, P = 0.0019 and 9 (4-24) g vs 17 (5-28) g, P = 0.002, respectively]. rFVIIa did not increase CFRs [3(0-9) vs |(0-5), P = 0.11]. CONCLUSION: rFVIIa led to a decrease in BT and microvascular bleeding but did not significantly affect arterial thrombosis in rabbits.  相似文献   
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BackgroundConventional histological analyses are the gold standard for the study of aneurysms and vascular pathologies in pre-clinical research. Over the past decade, in vivo and ex vivo imaging using multiphoton microscopy have emerged as powerful pre-clinical tools for detailed tissue analyses that can assess morphology, the extracellular matrix (ECM), cell density and vascularisation. Multiphoton microscopy allows for deeper tissue penetration with minor phototoxicity.ObjectiveThe present study aimed to demonstrate the current status of multimodality imaging, including multiphoton microscopy, for detailed analyses of neo-endothelialisation and ECM evolution after flow-diverter stent (FDS) treatment in an experimental rabbit model of aneurysms.MethodsMultiphoton microscopy tools for assessing autofluorescence and second harmonic generation (SHG) signals from biological tissues were used to evaluate the endovascular treatment of intracranial aneurysms in an animal model of aneurysms (pig, rabbit). Results from multiphoton microscopy were compared to those from standard histology, electronic and bright field microscopy.ConclusionsThe present study describes novel evaluation modes based on multiphoton microscopy for visualising tissue morphology (e.g., collagen, elastin, and cells) to qualify and quantify the extent of neo-intimal formation of covered arteries and device integration into the arterial wall using a rabbit model of intracranial aneurysms treated with FDS.  相似文献   
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Noroviruses and sapoviruses are members of the family Caliciviridae and emerging enteric pathogens of humans and animals. Since their discovery and characterization in swine, relatively few strains have been described in detail. In order to investigate their genetic diversity, a total of 266 fecal samples collected in the province of Quebec, Canada, between 2005 and 2007 were screened for the presence of caliciviruses by RT-PCR using broadly reactive primers. Genetically heterogeneous caliciviruses were detected on the majority of farms. Typical noroviruses related to known swine genotypes were present on 20% of the farms. Sapoviruses were detected on 75% of the farms and were the most heterogeneous group. Further characterization of selected strains in their 3′ end parts was carried out for their classification and unveiled possibly new clusters of sapoviruses. No human-like noroviruses or sapoviruses were detected in the present study. GenBank accession numbers of all sequences described in this study are indicated in the figure legends.  相似文献   
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We assessed the possible role in vivo CD4(+) CD8(+) T cells as a viral reservoir for simian immunodeficiency virus (SIV), in a macaque with 50% CD4(+) CD8(+) T cells in peripheral blood. During primary infection (day 14) of this rhesus macaque with the pathogenic SIVmac251 strain, proviruses were detected at similar frequencies in CD4(+) CD8(+) T cells (1/10) and CD4(+) T cells (1/10) and at a lower frequency in CD8(+) T cells (1/800). On day 235, no viral DNA was detected in CD8(+) cells, despite the persistent high viral load, indicating that CD8(+) cells do not constitute a reservoir during the chronic phase of SIV infection. Infection induced early lymphopenia of CD4(+), CD4(+) CD8(+), and CD8(+) cells; only the CD8(+) cell population returned to initial levels and expanded further. We found that CD4(+) CD8(+) T cells expressed the costimulatory CD28 molecule less and were more prone to die in vitro after phytohemagglutinin/interleukin 2 stimulation than were CD4(+) T cells. Taken together, massive death of CD4(+) CD8(+) T cells during acute stages of SIV infection may explain why CD8(+) T cells did not represent a major reservoir for SIV at the onset of infection.  相似文献   
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