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1.
Ascites is one of the earliest and most common complications of patients with cirrhosis. A typical circulatory dysfunction characterized by arterial vasodilation, high cardiac output and stimulation of vasoactive systems is commonly present in these patients and is associated with a poor prognosis. The treatment of ascites has been based on the combination of a low-sodium diet and the administration of diuretics. The reintroduction of paracentesis and the recent introduction of the transjugular intrahepatic portosystemic shunt (TIPS) are the most relevant innovations in the treatment of ascites during the past two decades, although controlled trials in large series of patients are needed to delineate whether TIPS is a safe and useful treatment for these patients.  相似文献   
2.
Thirty patients diagnosed with breast cancer were included in a prospective randomized study comparing the in vivo priming effect of bioequivalent doses of glycosylated (lenograstim) and nonglycosylated (filgrastim) rG-CSF administration. Analysis of the efficacy of equivalent biological doses of both rG-CSFs showed no significant differences either in the mobilization of the subpopulations of PBPC considered (CD34+, CD34+/38, CD34+/DR), the content of such CD34+ cell subsets in the leukapheresis product, or the cost of the mobilization and collection procedures between both recombinant molecules. These results suggest that priming with bioequivalent doses of the two commercially available forms of glycosylated or nonglycosylated rG-CSF has a similar in vivo effect on PBPC mobilization.  相似文献   
3.
The characteristics of ventricular fibrillatory signals vary as a function of the time elapsed from the onset of arrhythmia and the maneuvers used to maintain coronary perfusion. The dominant frequency (FrD) of the power spectrum of ventricular fibrillation (VF) is known to decrease after interrupting coronary perfusion, though the corresponding recovery process upon reestablishing coronary flow has not been quantified to date. With the aim of investigating the recovery of the FrD during reperfusion after a brief ischemic, period, 11 isolated and perfused rabbit heart preparations were used to analyze the signals obtained with three unipolar epicardial electrodes (E1-E3) and a bipolar electrode immersed in the thermostatizfid organ bath (E4), following the electrical induction of VF. Recordings were made under conditions of maintained coronary perfusion (5 min), upon interrupting perfusion (15 mini, and after reperfusion (5 min), FrD was determined using Welch's method. The variations in FrD were quantified during both ischemia and reperfusion, based on an exponential model AFrD = A exp (-t/C). During ischemia ΔFrD is the difference between FrD and the minimum value, while t is the time elapsed from the interruption of coronary perfusion. During reperfusion ΔFrD is the difference between the maximum value and FrD, while t is the time elapsed from the restoration of perfusion, A is one of the constants of the model, and C is the time constant. FrD exhibited respective initial values of 16.20 ± 1.67, 16.03 ± 1.38, and 16.03 ± 1.80 Hz in the epicardial leads, and 15.09 ±1.07 Hz in the bipolar lead within the bath. No significant variations were observed during maintained coronary perfusion. The fit of the FrD variations to the model during ischemia and reperfusion proved significant in nine experiments. The mean time constants C obtained on fitting to the model during ischemia were as follows: El =294.4 ± 75.6, E2 = 225.7 ± 48.5, E3 = 327.4 ± 79.7, and E4 = 298.7 ± 43.9 seconds. The mean values of C obtained during reperfusion, and the significance of the differences with respect to the ischemic period were: El = 57.5 ± 8.4 (P ± 0.01), E2 = 64.5 ± 11.2 (P0.01), E3 = 80.7 ± 13.3 (P < 0.01), and E4 = 74.9 ± 13.6 (P < 0.0001). The time course variations of the FrD of the VF power spectrum fit an exponential model during ischemia and reperfusion. The time constants of the model during reperfusion after a brief ischemic period are significantly shorter than those obtained during ischemia.  相似文献   
4.
Auditory event-related potentials (ERPs) were recorded from 71 healthy individuals between 18 and 82 years of age during performance of a disjunctive reaction time task in an auditory oddball paradigm. The effects of aging on reaction times and on the latencies, amplitudes, and distributions of each of the main ERP components were examined. No significant slowing of the reaction times of the elderly subjects was observed in relation to the younger ones. The peak latencies of both the N1 and P2 components elicited by standard tones were slightly but significantly slowed with age. In the ERPs of target tones, the later, endogenous components (N2, P3, and SW) showed linear increases in latency as a function of age; the later the component, the longer the age-related delay. In general, aging was associated with less negativity (both N2 and SW) and more positivity (P3) over the anterior scalp, together with a smaller P3 and a more pronounced N2 over posterior scalp areas. Most of the effects observed in target ERPs were also evident in the difference waves derived from subtraction of the standard from the target ERPs, although the slope of the age-related latency increase of N2 was shallower and that of the P3 was steeper in the difference ERPs. These findings are discussed in relation to previous accounts of ERP changes with aging.  相似文献   
5.
Summary. There are limited data on the prognostic role of biomarkers in anticoagulated patients with atrial fibrillation (AF). We evaluated the prognostic value of high sensitivity TnT (hsTnT) and high‐sensitivity interleukin‐6 (hsIL6) in a large cohort of AF patients taking oral anticoagulant therapy (OAC) as both biomarkers have been associated with adverse cardiovascular events. Methods: We studied 930 patients (51% male; median age 76) with permanent/ paroxysmal AF who were stabilized (for at least 6 months) on OAC (INRs 2.0–3.0). Plasma hsTnT and hsIL6 levels were quantified by electrochemiluminescense immunoassay at baseline. Patients were followed‐up for up to 2 years, and adverse events (thrombotic and vascular events, mortality and major bleeding) were recorded. Results: At follow‐up, 96 patients (3.97%/year) died whilst 107 had an adverse cardiovascular event (3.14%/year). On multivariate analysis, high hsTnT and high hsIL6 remained significantly associated with prognosis even after adjusting for CHADS2 score: HR 2.21 (1.46–3.35, P < 0.001) for high hsTnT and 1.97 (1.29–3.02, P = 0.002) for high hsIL6, for adverse cardiovascular events. For all‐cause mortality, the HRs were 1.79 (1.13–2.83, P = 0.013) and 2.48 (1.60–3.85, P < 0.001), respectively. The integrated discrimination index (IDI) values of clinical scores (CHADS2 and CHA2DS2‐VASc) were improved by the addition of hsTnT and/or hsIL6 (all P < 0.05). Conclusion: In a large ‘real world’ cohort of anticoagulated AF patients, both hsTnT and hsIL6 levels provided prognostic information that was complementary to clinical risk scores for prediction of long‐term cardiovascular events and death, suggesting that these biomarkers may potentially be used to refine clinical risk stratification in AF.  相似文献   
6.
Summary. Background: The metastable native conformation of serpins is required for their protease inhibition mechanism, but also renders them vulnerable to missense mutations that promote protein misfolding with pathological consequences. Objective: To characterize the first antithrombin deficiency caused by a large in‐frame insertion. Patients/Methods: Functional, biochemical and molecular analysis of the proband and relatives was performed. Recombinant antithrombin was expressed in HEK‐EBNA cells. Plasma and recombinant antithrombins were purified and sequenced by Edman degradation. The stability was evaluated by calorimetry. Reactive centre loop (RCL) exposure was determined by thrombin cleavage. Mutant antithrombin was crystallized as a dimer with latent plasma antithrombin. Results: The patient, with a spontaneous pulmonary embolism, belongs to a family with significant thrombotic history. We identified a complex heterozygous in‐frame insertion of 24 bp in SERPINC1, affecting strand 3 of β‐sheet A, a region highly conserved in serpins. Surprisingly, the insertion resulted in a type II antithrombin deficiency with heparin binding defect. The mutant antithrombin, with a molecular weight of 59 kDa, had a proteolytic cleavage at W49 but maintained the N‐terminal disulphide bonds, and was conformationally sensitive. The variant was non‐inhibitory. Analysis of the crystal structure of the hyperstable recombinant protein showed that the inserted sequence annealed into β‐sheet A as the fourth strand, and maintained a native RCL. Conclusions: This is the first case of a large in frame‐insertion that allows correct folding, glycosylation, and secretion of a serpin, resulting in a conformationally sensitive non‐inhibitory variant, which acquires a hyperstable conformation with a native RCL.  相似文献   
7.
8.
Background: There are no available statistical data about sudden cardiac death in Brazil. Therefore, this study has been conducted to evaluate the incidence of sudden cardiac death in our population and its implications. Methods: The research methodology was based on Thurstone's Law of Comparative Judgment, whose premise is that the more an A stimulus differs from a B stimulus, the greater will be the number of people who will perceive this difference. This technique allows an estimation of actual occurrences from subjective perceptions, when compared to official statistics. Data were collected through telephone interviews conducted with Primary and Secondary Care physicians of the Public Health Service in the Metropolitan Area of São Paulo (MASP). Results: In the period from October 19, 2009, to October 28, 2009, 196 interviews were conducted. The incidence of 21,270 cases of sudden cardiac death per year was estimated by linear regression analysis of the physicians’ responses and data from the Mortality Information System of the Brazilian Ministry of Health, with the following correlation and determination coefficients: r = 0.98 and r2= 0.95 (95% confidence interval 0.8–1.0, P < 0.05). The lack of waiting list for specialized care and socioadministrative problems were considered the main barriers to tertiary care access. Conclusions: The incidence of sudden cardiac death in the MASP is high, and it was estimated as being higher than all other causes of deaths; the extrapolation technique based on the physicians’ perceptions was validated; and the most important bureaucratic barriers to patient referral to tertiary care have been identified. (PACE 2012; 35:1326–1331)  相似文献   
9.
10.
BACKGROUND: The efficacy of oral anticoagulant therapy is largely conditioned by both environmental and genetic factors. Objectives: To attempt to define the genetic profile involved in the response to this treatment. PATIENTS AND METHODS: We selected 100 men younger than 75 years, with non-valvular atrial fibrillation, who started anticoagulation with acenocoumarol following the same protocol: 3 mg for three consecutive days. Then, doses were individually adjusted to achieve a steady International Normalized Ratio (INR). The basal plasma level and the level after 3 days were obtained, and the INR was determined. We studied five functional polymorphisms: FVII -323 Del/Ins, CYP2C*9, VKORC1 c1173t, calumenin (CALU) R4Q and CALU a29809g. The dose required for a steady INR was also recorded. RESULTS: Only the VKORC1 genotype had significant impact on the efficacy of therapy. Carriers of the 1173t allele were significantly more sensitive to therapy for 3 days [INR 2.07 (1.59-2.87) vs. 1.74 (1.30-2.09); P = 0.015] and they needed lower acenocoumarol doses to stabilize their INR (15.8 +/- 5.6 vs. 19.5 +/- 6.0 mg week(-1); P = 0.004). Its effect was exacerbated by combination with the CALU a29809g polymorphism. Carriers of both variants (27% of the sample) achieved the highest INR [2.26 (1.70-3.32)] and required the lowest dose (14.1 +/- 5.1 mg week(-1)). This genetic profile was particularly relevant in patients with INR >or= 3.5 at the start of therapy (P = 0.005; odds ratio = 6.67, 95% confidence interval = 1.32-37.43). CONCLUSIONS: Our results suggest that CALU a29809g might be a new genetic factor involved in the pharmacogenetics of anticoagulant therapy, and confirm that specific genetic profiles defined by different polymorphisms will determine the initial response and dose required to achieve a stable and safe INR.  相似文献   
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