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71.
Objectives Recently, direct stenting has been shown in retrospective and randomized studies to be feasible and safe in highly selected patients, with a potential interest to reduce the cost of the procedure and the rate of no-reflow. This randomized pilot study was designed to compare the incidence of no-reflow after direct stenting or conventional stenting after balloon predilation in acute coronary syndrome-related lesions. Methods and Results Between December 1998 and October 1999, 130 patients in our center with acute coronary syndromes were included in this study and randomized in 2 groups. In group A (n = 65), direct stent implantation was performed without balloon predilation. In group B (n = 65), conventional balloon predilation was carried out before stent implantation. Baseline clinical and angiographic characteristics before the procedure were similar in the 2 groups of patients. No-reflow was observed in 7.7% after direct stenting and in 6.1% after conventional stent implantation (P = not significant). The immediate clinical success rate was similar in the 2 groups. Among the procedural data, only duration of the procedure (shorter in the direct stenting group), the number of balloons used, and the quantity of contrast agent (lower in the direct stenting group) were significantly different between the 2 groups (P < .05). The 6-month clinical outcome was similar in the 2 groups. Conclusion This randomized study confirms the promising results of previous studies that show the feasibility and the safety of direct coronary stenting in highly selected acute coronary syndrome-related lesions. The major impact of this strategy is the improvement of the cost-benefit ratio, with no major influence on the acute complications and especially on the occurrence of no-reflow in this high-risk population. (Am Heart J 2002;143:1027-32.)  相似文献   
72.
The purpose of this study was to assess the feasibility and safety of direct coronary stenting in acute coronary syndromes using 5 Fr guiding catheters by transradial approach. A series of 119 patients with an acute coronary syndrome (unstable angina, n = 55; acute myocardial infarction, n = 45; recent acute myocardial infarction, n = 19) explored by transradial approach and eligible for direct stenting were included. A large proportion of patients (52%) was treated during the procedure by platelet IIb/IIIa receptor blockade. Only Medtronic 5 Fr guiding catheters were used in this study. Direct coronary stenting was attempted in all 119 highly selected patients. Failure of direct stenting was observed in only five cases (3.9%) and the stent successfully retrieved in each case in the 5 Fr guiding catheter. In these five cases, balloon predilation was performed and then the stent implanted successfully. Different stents were used: ACS stent (54%), AVE stent (33%), Velocity stent (10%), Nir stent (3%), with diameter ranging from 2.5 to 4 mm. In four cases, the dilation was finally performed using 6 Fr guiding catheters because the backup of the 5 Fr catheter was considered to be too low (3%). No vascular access site complications occurred in this series of patients. We conclude that direct coronary stenting using transradial approach and 5 Fr guiding catheters yields excellent procedural success rate. In the setting of acute coronary syndromes requiring platelet IIb/IIIa receptor blockade or after failure of thrombolysis, this mini-invasive strategy is very attractive because of the low risk of access site complications.  相似文献   
73.
OBJECTIVES: We sought to compare, through a meta-analytic process, the transradial and transfemoral approaches for coronary procedures in terms of clinical and procedural outcomes. BACKGROUND: The radial approach has been increasingly used as an alternative to femoral access. Several trials have compared these two approaches, with inconclusive results. METHODS: The MEDLINE, CENTRAL, and conference proceedings from major cardiologic associations were searched. Random-effect odds ratios (ORs) for failure of the procedure (crossover to different entry site or impossibility to perform the planned procedure), entry site complications (major hematoma, vascular surgery, or arteriovenous fistula), and major adverse cardiovascular events (MACE), defined as death, myocardial infarction, emergency revascularization, or stroke, were computed. RESULTS: Twelve randomized trials (n = 3,224) were included in the analysis. The risk of MACE was similar for the radial versus femoral approach (OR 0.92, 95% confidence interval [CI] 0.57 to 1.48; p = 0.7). Instead, radial access was associated with a significantly lower rate of entry site complications (OR 0.20, 95% CI 0.09 to 0.42; p < 0.0001), even if at the price of a higher rate of procedural failure (OR 3.30, 95% CI 1.63 to 6.71; p < 0.001). CONCLUSIONS: The radial approach for coronary procedures appears as a safe alternative to femoral access. Moreover, radial access virtually eliminates local vascular complications, thanks to a time-sparing hemostasis technique. However, gaining radial access requires higher technical skills, thus yielding an overall lower success rate. Nonetheless, a clear ongoing trend toward equalization of the two procedures, in terms of procedural success, is evident through the years, probably due to technologic progress of materials and increased operator experience.  相似文献   
74.
Home management of malaria is recommended for prompt, effective antimalarial treatment in children less than five years of age. Compliance, safety, and effectiveness of the new fixed-dose artesunate-amodiaquine regimen used to treat suspected malaria were assessed in febrile children enrolled in a 24-month cohort study in two settings in Madagascar. Children with fever were asked to visit community health workers. Presumptive antimalarial treatment was given and further visits were scheduled for follow-up. The primary endpoint was the risk of clinical/parasitologic treatment failure. Secondary outcomes included fever/parasite clearance, change in hemoglobin levels, and frequency of adverse events. The global clinical cure rate was 98.4% by day 28 and 97.9% by day 42. Reported compliance was 83.4%. No severe adverse effects were observed. This study provides comprehensive data concerning the clinical cure rate obtained with artesunate-amodiaquine and evidence supporting the scaling up of home management of malaria.  相似文献   
75.

Background

The long-term prognostic value of heart rate recovery (HRR) has been incompletely documented in patients with coronary artery disease (CAD). We sought to confirm the prognostic value of HRR in a large cohort with stable CAD.

Methods

From the Coronary Artery Surgery Study registry, a database of 24,958 patients with CAD who underwent cardiac catheterization between 1974 and 1979, we identified 4097 patients with baseline exercise stress testing data. HRR was measured at 3 minutes post exercise during a passive recovery. Clinical outcomes were evaluated according to HRR in both threshold and continuous models.

Results

Median long-term follow-up was 14.7 years (interquartile range, 9.8-16.2). HRR < 46 beats per minute (Bpm) most appropriately differentiated nonsurvivors from survivors (area under receiver operating characteristic curve = 0.613) and was associated with an increased risk of all-cause death (adjusted hazard ratio = 1.15; P = 0.011). Increasing HRR was associated with a lower risk of all-cause (adjusted hazard ratio = 0.94 per 10 Bpm; 95% confidence interval, 0.91-0.97; P = 0.0005) and cardiovascular (CV) mortality (adjusted hazard ratio = 0.94 per 10 Bpm; 95% confidence interval, 0.90-0.98; P = 0.003).

Conclusions

HRR at 3 minutes independently predicts long-term all-cause and CV mortality in patients with stable CAD. Measurement of HRR at 3 minutes during passive recovery can be used as a complementary tool to identify patients with a higher total and CV risk.  相似文献   
76.
Background: Patients with ambulatory electrocardiographic (AECG) ST-segment depression and critical coronary narrowing are known to be at increased risk for adverse outcome, but little is known about patients with AECG ST-segment depression without critical coronary narrowing. Hypothesis: The objectives of this study were to characterize the coronary angiographic pathology in patients with AECG ST-segment depression but without critical (< 50% di-ameter stenosis) coronary narrowing and to compare demographic and clinical findings in these patients with those enrolled in the Asymptomatic Cardiac Ischemia Pilot Study with AECG ST-segment depression and critical (≥50% diameter stenosis) coronary narrowing. Methods: Coronary angiograms from patients with AECG ST-segment depression were reviewed in a central laboratory and quantitative measurement of percent stenosis was performed. Clinical and angiographic comparisons were made between patients with and without critical coronary narrowing. Results: Patients without critical coronary narrowing (n = 64) were younger (p = 0.02), less likely to be male (p < 0.001) or to have risk factors for coronary atherosclerosis or a history of myocardial infarction (p < 0.001), and had fewer ischemic episodes per 24 h on the screening AECG (p = 0.02) than patients with critical coronary narrowing (n = 441). Of patients without critical narrowing, one half had angiographic evidence for coronary artery disease (≥ 20% stenosis) and 60% had an ejection fraction > 70%. Conculsions: Patients with AECG ST-segment depression without critical coronary narrowing are heterogeneous, with half having measurable coronary artery disease. Demographically and clinically, they appear to be different than patients with AECG ST-segment depression with critical coronary narrowing.  相似文献   
77.
Angiogenesis, the process of development of a new microvasculature, is regulated by a balance of positive and negative factors. We show both in vivo and in vitro that the members of the human prolactin/growth hormone family, i.e., human prolactin, human growth hormone, human placental lactogen, and human growth hormone variant are angiogenic whereas their respective 16-kDa N-terminal fragments are antiangiogenic. The opposite actions are regulated in part via activation or inhibition of mitogen-activated protein kinase signaling pathway. In addition, the N-terminal fragments stimulate expression of type 1 plasminogen activator inhibitor whereas the intact molecules have no effect, an observation consistent with the fragments acting via separate receptors. The concept that a single molecule encodes both angiogenic and antiangiogenic peptides represents an efficient model for regulating the balance of positive and negative factors controlling angiogenesis. This hypothesis has potential physiological importance for the control of the vascular connection between the fetal and maternal circulations in the placenta, where human prolactin, human placental lactogen, and human growth hormone variant are expressed.  相似文献   
78.
Xylella fastidiosa (Xf) is a plant pathogen causing significant losses in agriculture worldwide. Originating from America, this bacterium caused recent epidemics in southern Europe and is thus considered an emerging pathogen. As the European regulations do not authorize antibiotic treatment in plants, alternative treatments are urgently needed to control the spread of the pathogen and eventually to cure infected crops. One such alternative is the use of phage therapy, developed more than 100 years ago to cure human dysentery and nowadays adapted to agriculture. The first step towards phage therapy is the isolation of the appropriate bacteriophages. With this goal, we searched for phages able to infect Xf strains that are endemic in the Mediterranean area. However, as Xf is truly a fastidious organism, we chose the phylogenetically closest and relatively fast-growing organism X. albineans as a surrogate host for the isolation step. Our results showed the isolation from various sources and preliminary characterization of several phages active on different Xf strains, namely, from the fastidiosa (Xff), multiplex (Xfm), and pauca (Xfp) subspecies, as well as on X. albilineans. We sequenced their genomes, described their genomic features, and provided a phylogeny analysis that allowed us to propose new taxonomic elements. Among the 14 genomes sequenced, we could identify two new phage species, belonging to two new genera of the Caudoviricetes order, namely, Usmevirus (Podoviridae family) and Subavirus (Siphoviridae family). Interestingly, no specific phages could be isolated from infected plant samples, whereas one was isolated from vector insects captured in a contaminated area, and several from surface and sewage waters from the Marseille area.  相似文献   
79.
Angiogenesis is a crucial step in many pathologies, including tumor growth and metastasis. Here, we show that tilted peptides exert antiangiogenic activity. Tilted (or oblique-oriented) peptides are short peptides known to destabilize membranes and lipid cores and characterized by an asymmetric distribution of hydrophobic residues along the axis when helical. We have previously shown that 16-kDa fragments of the human prolactin/growth hormone (PRL/GH) family members are potent angiogenesis inhibitors. Here, we demonstrate that all these fragments possess a 14-aa sequence having the characteristics of a tilted peptide. The tilted peptides of human prolactin and human growth hormone induce endothelial cell apoptosis, inhibit endothelial cell proliferation, and inhibit capillary formation both in vitro and in vivo. These antiangiogenic effects are abolished when the peptides' hydrophobicity gradient is altered by mutation. We further demonstrate that the well known tilted peptides of simian immunodeficiency virus gp32 and Alzheimer's beta-amyloid peptide are also angiogenesis inhibitors. Taken together, these results point to a potential new role for tilted peptides in regulating angiogenesis.  相似文献   
80.
Liver steatosis is a common finding in patients infected with hepatitis C virus (HCV). Host and viral factors have been associated with steatosis, but their relative contributions have not been clearly addressed. It has been suggested that steatosis plays a role in the progression of liver fibrosis. AIMS: To assess: a) factors associated with steatosis in patients infected with hepatitis C virus; b) their impact on liver fibrosis. PATIENTS AND METHODS: Three hundred and fourteen untreated patients were included. Lifetime alcohol consumption was estimated. Liver fibrosis, inflammation and necrosis were assessed using the METAVIR score. Body mass index (BMI) was determined. The scoring system for steatosis was as follows: 0, no steatosis; 1, less than 10%; 2, 10% to 30%; 3, 30% to 70%; 4, more than 70% of hepatocytes affected. RESULTS: In univariate analysis, steatosis was associated with elevated BMI (P=0.001), excessive alcohol intake (P=0.005), genotype 3 (P<0.001) and moderate to severe histological activity (P=0.01). Multivariate analysis showed that steatosis correlated with two independent factors: genotype 3a (OR=60.7; 95% CI: 7.6-483.4) (P<0.001) and BMI (OR=4.86; 95% CI: 1.8-13.15) (P=0.002). In univariate analysis, severe fibrosis (F2-F3-F4) was associated with older age (P<10(-5)), male gender (P=0.001), disease duration (P<0.006), BMI (P<10(-4)), alcohol intake (P<10(-6)), severity of histological activity (P<10(-5)) and steatosis (P<10(-6)). In multivariate analysis, three independent factors were associated with severe fibrosis: disease duration > 10 years (OR=3.17; 95% CI: 0.65-15.4) (P=0.015), presence of steatosis (OR=3.17; 95% CI: 1-9.99) (P<0.049) and genotype 3a (OR=5.56; 95% CI: 1.4-22.1) (P=0.015). CONCLUSION: In patients with chronic hepatitis C, steatosis is significantly associated with genotype 3 infection and high BMI. Steatosis is an independent risk factor associated with severe fibrosis. These results have major implications for the management of patients with chronic hepatitis C.  相似文献   
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