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71.
OBJECTIVES: The aim of this study was to assess the potential value of hand-carried ultrasound (HCU) devices in the diagnosis and follow-up of patients with pleural effusion (PE) after cardiac surgery. METHODS: Seventy consecutive patients were evaluated at bedside early after cardiac surgery, in the upright sitting position, using an HCU device on hospital admission and every 3 days until hospital discharge. The posterior chest wall was scanned along the paravertebral, scapular, and posterior axillary lines. For each hemithorax, an effusion index was derived as the sum of the intercostal spaces between the lower and upper limits of the PE along the lines of scanning, divided by 3. A standard chest radiograph was performed in all patients on hospital admission and at hospital discharge, and was qualitatively scored (0, absent; 1, small; 2, large PE). The findings of the HCU device and radiograph were compared using kappa statistics and the Kruskal-Wallis test. RESULTS: A chest ultrasound was feasible in all patients (mean [+/- SD] time, 5 +/- 2 min). Compared with the chest ultrasound, a physical examination showed a sensitivity of 69% and a specificity of 77%. On hospital admission, the HCU device detected a PE in 72 of 140 hemithoraxes. Agreement with the finding of the radiograph was 76% (kappa = 0.52). In 15 hemithoraxes, the HCU device revealed a PE that had not been diagnosed using the radiograph. Conversely, in 18 hemithoraxes a PE that had been diagnosed with a radiograph was not confirmed by the HCU device. The correlation between ultrasound and radiographic scores was statistically significant (p < 0.001). At hospital discharge, a PE was present in 31 of 140 hemithoraxes according to the findings of the HCU device, and in 38 of 140 hemithoraxes according to the findings of the radiograph (agreement, 78%; kappa = 0.44). CONCLUSIONS: In patients early after cardiac surgery, HCU devices allow rapid PE detection and improve the clinical diagnosis. Compared to a radiograph, this method offers the unique advantage of the bedside evaluation of patients without the need for radiation exposure.  相似文献   
72.
Percutaneous revascularization of saphenous vein grafts (SVGs) remains a challenging task. Drug-eluting stents (DESs) have been shown to decrease the incidence of restenosis in de novo native coronary artery lesions. However, their clinical value in SVGs remains to be established. We compared long-term clinical outcomes of percutaneous coronary intervention with DESs and bare metal stents (BMSs) for de novo lesions in SVGs. In a large prospective, multicenter registry, 360 patients underwent stenting of a de novo lesion in SVGs using BMSs (288 patients) or DESs (72 patients). Incidence of major adverse cardiac events (MACEs), including all-cause mortality, reinfarction, and target vessel revascularization, was recorded at a 12-month follow-up. Compared with the DES group, patients receiving BMSs were more likely to be men, to have chronic renal insufficiency or higher Charlson scores, but less likely to have undergone previous percutaneous coronary intervention. Incidence of MACEs at 12-month follow-up was similar in the 2 groups (17.8% in DES group vs 20.3% in BMS group, respectively, p = 0.460). Cox regression analysis identified age, chronic renal failure, cardiogenic shock at presentation, and ostial location of stenosis as independent predictors of long-term MACEs. In conclusion, our data suggest that rates of 12-month MACEs associated with the use of DESs and BMSs are similar in patients undergoing treatment of de novo lesions in SVGs.  相似文献   
73.
Sarcoidosis is thought to result from the interaction between an unknown environmental antigenic trigger and the host's genetic susceptibility. We hypothesized that sarcoidosis, or one of the disease subsets, could be associated with single nucleotide polymorphisms of C-C chemokine receptor 2 (CCR2) gene. Eight single-nucleotide polymorphisms in CCR2 were studied in a total of 304 Dutch individuals (90 non-L?fgren sarcoidosis, 47 L?fgren's syndrome, 167 control subjects). From the investigated CCR2 polymorphisms, nine haplotypes were deduced (haplotypes 1-9). In patients with L?fgren's syndrome, a strongly significant increase in the frequency of CCR2-haplotype 2, which includes four unique alleles (A at nucleotide position -6752, A at 3,000, T at 3,547, and T at 4,385), was observed compared with control subjects (74% vs. 38% respectively, p < 0.0001), whereas no difference was found between non-L?fgren sarcoidosis and control subjects (both 38%). The association between CCR2-haplotype 2 carriage frequency and L?fgren's syndrome (odds ratio, 4.4; p < 0.0001) remained significant after adjustment for human leukocyte antigen haplotype DRB1*0301-DQB1*0201 (odds ratio, 11.5; p < 0.0001) and female sex (odds ratio, 3.2; p = 0.003), two known risk factors for L?fgren's syndrome. In conclusion, this report describes a strong association between CCR2-haplotype 2 and L?fgren's syndrome. Further studies are needed to understand the molecular mechanisms underlying this association.  相似文献   
74.
AIMS: In human atrial myocytes (HuAM) two beta-adrenergic receptors (beta-AR) and four splicing-variants of the serotonin 5-HT(4) receptor are present. Multiple coupling with G stimulatory (G(s)) and G inhibitory (G(i)) proteins has been proposed for both beta(2)-AR and 5-HT((4b)) subtypes, but no functional data exist in HuAM. Serotonin (5-HT) and catecholamines are able to trigger arrhythmias in human atrium, but the underlying cellular mechanisms are not completely understood. The pacemaker current (I(f)) is an inward Na(+)/K(+) current, constitutively present in HuAM and directly modulated by cAMP; I(f) could play a role in triggering human atrial arrhythmias. This study evaluated the different G protein coupling of beta(1)-AR, beta(2)-AR and 5-HT(4) receptors by assessing the modulation of I(f) by selective stimuli. METHODS: HuAM were isolated from right atrial appendages and utilized for patch-clamp recording. The coupling of receptor subtypes with G(i) proteins was tested by incubating HuAM in pertussis toxin (PTX). RESULTS: Beta(1)-AR stimulation (Isoprenaline [ISO] + ICI 118,551), and 5-HT caused a concentration-dependent significant shift of the half activation potential of I(f) activation curve (DeltaV(h)), P < 0.01. beta(2)-AR stimulation (ISO 1 microM + CGP 20712A) also significantly shifted V(h) (P < 0.0001), but with DeltaV(h)[beta(2)-AR] significantly smaller than the effect caused by 1 microM beta(1)-AR stimulation (P < 0.05). Pre-treatment of HuAM with PTX did not alter the effect of beta(1)-AR stimulation (both 0.1 and 1 microM) and 1 microM 5-HT on I(f), but significantly increased the effect in response to beta(2)-AR stimulation and 0.1 microM 5-HT (P < 0.05 for both), thus suggesting a G(i) protein coupling of these receptors. CONCLUSIONS: Our results provide the first functional evidence of the different G protein coupling of beta(1)-AR, beta(2)-AR and 5-HT(4) receptors in HuAM. Further they support the view that I(f) current might play an important role in triggering catecholamines and serotonin-induced atrial arrhythmias.  相似文献   
75.
76.
Non-myeloablative stem cell transplantation (NMT) has been increasingly used in compromised patients who would otherwise have been unable to undergo allotransplant. There is little understanding of the kinetics of immune reconstitution and its influence on infective complications following NMT. The aim of present study was to evaluate lymphocyte subset reconstitution over the first 12 months post-transplant in 15 adult patients receiving NMT with comparison to that of 30 patients grafted with a conventional hemopoietic stem cell transplantation (HSCT). NMT recipients were conditioned with fludarabine-based conditioning regimens. Peripheral blood stem cell (PBSC) was the source of stem cells in 13 NMT recipients and in 24 conventional HSCT recipients. Absolute numbers of helper (CD4+) T cells, naive (CD4+ CD45RA+) and memory (CD4+ CD45RO+) T cells as well as suppressor (CD8+) T cells, CD19+ B cells and NK cells were comparable in the two groups at all time points after transplantation. A median value of 200 CD4+ T cells/microl was achieved at 2 months post-transplant by the NMT and HSCT recipients. The CD4:CD8 ratio remained severely depressed throughout the study period. Almost all CD4+ lymphocytes expressed CD45RO antigen in the both groups of patients B lymphocytes showed low counts throughout the entire study period in both groups. Bacteremia and CMV antigenemia occurred respectively in 13 and 36% of the patients in the NMT group and in 15 and 39% of the patients in the HSCT group. Our preliminary data indicate that patients receiving a NMT have a lymphocyte reconstitution similar to that observed in patients who received a conventional HSCT. The incidence of bacteremia and CMV infection were not significantly different between the groups. Nevertheless, due to the small sample size, these results should be considered suggestive rather than definitive.  相似文献   
77.
COVID-19 is causing a high influx of patients suffering from serious respiratory complications leading the necessity to find effective therapies. These patients seem to present with cytokine perturbation and high levels of IL6. Tocilizumab and sarilumab could be effective in this condition.We retrospectively collected data about 112 consecutive hospitalized in a single center.Fifty (IL6 group) treated with tocilizumab (8 mg/kg intravenously [IV], 2 infusions 12 hours apart) or sarilumab 400 mg IV once and 62 treated with the standard of care but not anti-cytokine drugs (CONTROL group).To determine whether anti-IL6 drugs are effective in improving prognosis and reducing hospitalization times and mortality in COVID-19 pneumonia.To date 84% (42/50) of IL6 group patients have already been discharged and only 2/50 are still recovered and intubated in intensive care. Six/fifty patients (12%) died: 5/6 due to severe respiratory failure within a framework of severe acute respiratory distress syndrome (ARDS), 1 suffered an acute myocardial infarction, and 1 died of massive pulmonary thromboembolism. There were no adverse treatment events or infectious complications. Compared to the CONTROL group they showed a lower mortality rate (12% versus 43%), for the same number of complications and days of hospitalization.Anti-IL6 drugs seem to be effective in the treatment of medium to severe forms of COVID-19 pneumonia reducing the risk of mortality due to multi-organ failure, acting at the systemic level and reducing inflammation levels and therefore microvascular complications. However, it is essential to identify the best time for treatment, which, if delayed, is rendered useless as well as counterproductive. Further studies and ongoing clinical trials will help us to better define patients eligible as candidates for more aggressive intervention.  相似文献   
78.
79.
OBJECTIVE: Impaired diastolic function and left ventricular hypertrophy can occur early in the natural history of essential hypertension. High circulating levels of endogenous ouabain (EO) have been described in essential hypertension and have also been associated with left ventricular hypertrophy. The aim of this study was to investigate whether these cardiac modifications are related to plasma EO levels in the offspring of hypertensive families. METHODS: The study involved 41 subjects with (FAM+) and 45 subjects without (FAM-) a family history of hypertension. Arterial blood pressure, left ventricular geometry and function, and plasma EO levels were measured in each subject. RESULTS: Plasma EO levels were higher in the FAM+ subjects (221.5 +/- 10.95 versus 179.6 +/- 9.58 pmol/l, P = 0.004), and directly correlated with both systolic (r = 0.417, P < 0.0001) and diastolic blood pressure (r = 0.333, P = 0.002). Plasma EO was inversely related to an index of cardiac diastolic function determined as the ratio between the early and late peak flow velocity (r = -0.286, P = 0.012) and isovolumetric relaxation time (IVRT) (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, correlated with the IVRT (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, whereas the other echocardiographic parameters were similar to FAM-. CONCLUSIONS: Among the offspring of families with a positive history of hypertension, circulating EO levels and blood pressure are increased. Plasma EO levels are related to alterations of some indexes of diastolic heart function in these individuals.  相似文献   
80.
Cytohesin-1, a protein abundant in cells of the immune system, has been proposed to be a human homolog of the Saccharomyces cerevisiae Sec7 gene product, which is crucial in protein transport. More recently, the same protein has been reported to be a regulatory factor for the αLβ2 integrin in lymphocytes. Overexpression of human or yeast ADP-ribosylation factor (ARF) genes rescues yeast with Sec7 defects, restoring secretory pathway function. ARFs, 20-kDa guanine nucleotide-binding proteins initially identified by their ability to stimulate cholera toxin ADP-ribosyltransferase activity and now recognized as critical components in intracellular vesicular transport, exist in an inactive cytosolic form with GDP bound (ARF-GDP). Interaction with a guanine nucleotide-exchange protein (GEP) accelerates exchange of GDP for GTP, producing the active ARF-GTP. Both soluble and particulate GEPs have been described. To define better the interaction between ARF and Sec7-related proteins, effects of cytohesin-1, synthesized in Escherichia coli, on ARF activity were evaluated. Cytohesin-1 enhanced binding of 35S-labeled guanosine 5′-[γ-thio]triphosphate [35S]GTP[γS] or [3H]GDP to ARF purified from bovine brain (i.e., it appeared to function as an ARF-GEP). Addition of cytohesin-1 to ARF3 with [35S]GTP[γS] bound, accelerated [35S]GTP[γS] release to a similar degree in the presence of unlabeled GDP or GTP[γS] and to a lesser degree with GDP[βS]; release was negligible without added nucleotide. Cytohesin-1 also increased ARF1 binding to a Golgi fraction, but its effect was not inhibited by brefeldin A (BFA), a drug that reversibly inhibits Golgi function. In this regard, it differs from a recently reported BFA-sensitive ARF-GEP that contains a Sec7 domain.  相似文献   
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