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991.
Objective: To examine practices of French intensivists regarding the management of mechanically ventilated patients with Candida-positive airway specimens but no major risk factors for immunodepression. Design: Closed-item questionnaire with a clinical vignette. Setting: 564 French intensive care units (ICUs). Participants: 198 intensivists who have a special interest in infectious diseases and who answered the questionnaire (response rate, 35.1%). Intervention: None. Measurements and results: The respondents recommended bronchoalveolar lavage (62.6% of respondents), protected distal sampling and protected specimen brush (59.1%), transbronchial biopsy (38.9%), and tracheal aspiration (12.1%) for the diagnosis of candidal pneumonia. A positive airway specimen was felt by most respondents (83.3%) to indicate colonisation; 66.7% of respondents recommended tests for systemic candidiasis in this situation, and 56.5% serial sampling to compute the colonisation index. Azole derivatives were the preferred antifungal medications. The clinical vignette described a patient with chronic obstructive lung disease who required mechanical ventilation for an acute exacerbation and who had a tracheal aspirate positive for Candida. Responses varied widely, with 37.8% of respondents diagnosing clinically insignificant colonisation but 24.2% recommending antifungal treatment and 61.6% serial testing to assess the Candida colonisation index. Intensivists with greater experience with severely immunocompromised patients were more aggressive in their diagnostic management. Conclusions: Wide variations occur among practices of French intensivists regarding Candida-positive airway specimens in patients without major risk factors for immunodepression. Additional studies are needed to improve our understanding of the links between Candida colonisation and infection and to determine the indications for pre-emptive antifungal treatment in non-neutropenic critically ill patients.Presented in January 2002 at the congress of the French Society of Critical Care Medicine  相似文献   
992.
993.
Adult T-cell leukemia/lymphoma (ATL) is an aggressive lymphoid proliferative disease that exists under diverse clinical forms ranging from chronic to acute. Although leukemic cells from patients with ATL exhibit an intrinsic resistance to chemotherapy, monoclonal antibodies directed against CD25 (interleukin 2 receptor alpha [IL-2Ralpha] antibody) have been used as specific therapeutic agents. However, significant clinical results with these antibodies have been demonstrated only in chronic forms of ATL. In contrast to resting T cells, human T-cell lymphotropic virus type 1 (HTLV-1)-infected cells constitutively express high levels of surface transferrin receptor (TfR). Herein, we report the characterization of a new monoclonal antibody (mAb A24) directed against the human TfR and the evaluation of its capacity to block the proliferation of ATL cells ex vivo. We determined that A24 binds TfR with an equilibrium constant (K'd) of 2.7 nM and competes with transferrin for binding to TfR. A24 also inhibited [55Fe]-transferrin uptake in activated T cells and blocked T-cell proliferation. Moreover, A24 reduced and impaired TfR expression and recycling, respectively. Most important, we showed that A24 blocked the ex vivo proliferation of malignant T cells from both acute and chronic forms of ATL, through induction of programmed cell death. Therefore efficient therapeutic tools to treat acute forms of ATL might be derived from A24.  相似文献   
994.
995.
We evaluated the outcomes of 177 consecutive patients (43 women, 134 men) <40 years of age with premature atherosclerosis who underwent percutaneous coronary intervention. Women were younger, had more diabetes mellitus (37% vs 10%; p <0.001), but less hyperlipidemia (58% vs 75%; p <0.001) compared with men. In-hospital vascular complications and 1-year mortality rate or Q-wave myocardial infarction (7.9% vs 0.08%, p <0.01) were higher in women. By multivariable regression analysis, female gender was the only independent predictor of vascular complications (odds ratio, 14.1; 95% confidence intervals, 1.59 to 125, p = 0.01) and of 1-year mortality rate or nonfatal myocardial infarction (odds ratio, 12.5; 95% confidence interval, 1.14 to 111, p = 0.03). Women with premature coronary disease had a distinctive risk factor profile relative to men, with a predominance of diabetes and hypercholesterolemia, and were at higher risk of developing vascular and ischemic complications after percutaneous coronary intervention, warranting aggressive risk factor modification and vigilance in this population.  相似文献   
996.
Objective—Obstruction of the venous pathways after Mustard repair for transposition of the great arteries is associated with an increased risk of arrhythmia and sudden death. The purpose of this study was to assess the effectiveness of the largest (tracheal 22 × 40 mm) Wallstents in treating baffle obstructions.
Design—Retrospective analysis of patients with stented venous pathways.
Subjects—Eleven patients with baffle obstruction after Mustard repair for transposition of the great arteries.
Interventions—Stenoses were dilated with an 18 or 20 mm balloon. However, recoil was noticed in 11 patients: immediately (n = 7) or on repeat angiography (n = 4). Eighteen stents were implanted (mean (SD)) 18 (3.3) years postoperatively. After dilatation a tracheal Wallstent (11.5 F) was deployed.
Main outcome measures—Relief of obstruction, haemodynamic improvement.
Results—In the inferior vena cava, 10 stents were deployed in seven baffle obstructions with an increase in diameter from 9.8 (2.4) mm to 16.5 (1.4) mm (p < 0.01) and a mean (SD) pressure gradient decrease from 5.1 (3.6) mm Hg to 1.4 (2.0) mm Hg; in the superior vena cava, eight stents were implanted increasing the diameter from 9.1 (3.7) mm to 15.6 (3.8) mm (p < 0.001) with a decrease in mean pressure gradient from 5.1 (2.7) mm Hg to 1.9 (1.5) mm Hg. No complications were experienced during implantation. No anticoagulation was prescribed. During follow up (1.7 (0.6) years; range, 0.9-2.6) no problems were noted; five patients were re-catheterised without change in measurements. There was no evidence of peal formation in any of the stents.
Conclusion—It is concluded that Wallstents are safe, easy to use, and effective in relieving baffle obstruction. Anticoagulation does not seem neccessary.

Keywords: Mustard procedure;  venous baffle obstruction;  stent  相似文献   
997.

Purpose

Very few data are available about the clinical relevance of magnetic resonance (MR) imaging in preoperative evaluation of rectal villous adenoma. The aim is to evaluate the impact of MR imaging for the surgical management of rectal villous adenoma treated by transanal endoscopic microsurgery (TEM).

Methods

All patients with histologically proven rectal villous tumours operated by TEM who had a preoperative MR imaging between 2009 and 2017 were retrospectively reviewed. All patients underwent TEM because preoperative evaluation suggested systematically usT0 or usT1 tumour. Pathological stage was blindly compared to preoperative MR imaging (location according to the anal verge and the peritoneal reflection, amount of circumferential involvement, tumour size and staging) and preoperative transrectal ultrasonography (TRUS) results.

Results

Forty-five patients were included (24 men, mean age 65?±?8 years) with TRUS data available only in 37. Pathologic results were pT0-pTis in 32, pT1 in 10 and pT2 in 3. TRUS diagnosed correctly 36/37 lesions (97%) and understaged one pT2 tumour. A significant correlation between TRUS and pathologic results was noted (r?=?0.99; p?=?0.01). MR imaging diagnosed correctly 19/42 pTis-T1 and 1/3 pT2 tumours (46%). Overstaging by MR imaging was noted in 25 cases (54%). No correlation between MR imaging and pathologic results was noted (r?=?0.7; p?=?0.3).

Conclusion

Preoperative evaluation of rectal villous adenoma is overstaged by MRI in more than half of the patients. This study suggests that the indication of local excision by TEM for rectal villous adenoma should be based on TRUS rather than on MRI.
  相似文献   
998.
999.
A form of alpha-galactosylceramide, KRN7000, activates CD1d-restricted Valpha14-invariant (Valpha14i) natural killer (NK) T cells and initiates multiple downstream immune reactions. We report that substituting the C26:0 N-acyl chain of KRN7000 with shorter, unsaturated fatty acids modifies the outcome of Valpha14i NKT cell activation. One analogue containing a diunsaturated C20 fatty acid (C20:2) potently induced a T helper type 2-biased cytokine response, with diminished IFN-gamma production and reduced Valpha14i NKT cell expansion. C20:2 also exhibited less stringent requirements for loading onto CD1d than KRN7000, suggesting a mechanism for the immunomodulatory properties of this lipid. The differential cellular response elicited by this class of Valpha14i NKT cell agonists may prove to be useful in immunotherapeutic applications.  相似文献   
1000.
BACKGROUND: The impact of metabolic syndrome after acute myocardial infarction (AMI) has not yet been studied. In a population-based sample of patients with AMI, we sought to determine the prevalence of metabolic syndrome in patients with AMI, its impact on hospital outcomes, and to assess the relative influence of each of the components of the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III definition of metabolic syndrome on the risk of death and heart failure. METHODS: A total of 633 unselected, consecutive patients hospitalized with AMI were categorized according to the NCEP ATP III metabolic syndrome criteria (presence of >/=3 of the following: hyperglycemia; triglyceride level >/=150 mg/dL [>/=1.7 mmol/L]; high-density lipoprotein cholesterol level <40 mg/dL [<1.04 mmol/L] in men and <50 mg/dL [<1.30 mmol/L] in women; blood pressure >/=130/85 mm Hg; and waist circumference >102 cm in men or 88 cm in women). RESULTS: Among the 633 patients, 290 (46%) fulfilled the criteria for metabolic syndrome. Patients with metabolic syndrome were older and more likely to be women. Acute myocardial infarction characteristics and left ventricular ejection fraction rates were similar for both groups. In-hospital case fatality was higher in patients with metabolic syndrome compared with those without, as was the incidence of severe heart failure (Killip class >II). In multivariate analysis, metabolic syndrome was a strong and independent predictor of severe heart failure, but not in-hospital death. Analysis of the predictive value of each of the 5 metabolic syndrome components for severe heart failure showed that hyperglycemia was the major determinant (odds ratio, 3.31; 95% confidence interval, 1.86-5.87). CONCLUSIONS: In an unselected population of patients with AMI, the prevalence of metabolic syndrome was high. Metabolic syndrome appeared associated with worse in-hospital outcome, with a higher risk of development of severe heart failure. Among metabolic syndrome components, hyperglycemia was the main correlate of the risk of development of severe heart failure during AMI.  相似文献   
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