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1.
PURPOSE: To evaluate the effect of aspirin treatment upon fetal loss in mice with experimental antiphospholipid syndrome (APLS). MATERIALS AND METHODS: Experimental APLS was induced in pregnant mice by passive transfer of mouse monoclonal anticardiolipin antibody. The mice were treated with high (100μg/d) or low (10μg/d) does of aspirin, using vitaminC(100μg/d or 10μg/d)as a control. The mice were assessed for the presence of lupus anticoagulants (prolonged aPTT), thrombocytopenia, degree of fetal resorption rate and mean embryo and placental weights. RESULTS: The mice with APLS had a higher fetal resorption rate(45.7± 12.2% vs 2.5 ± 0.4%, P<0.001), reduced placenta mean weight(104 ± 8 mgvs 169 ±7mg, P<0.001), prolonged aPTT (94± 14sec vs 39±4sec, P<0.001), and reduced mean platelet count(597± 186 ± 103/mm3vs 847±51 ± 103/mm3,P<0.001). The groupof mice with APLS, who were treated with low-dose aspirin, had a lower resorption rate (11.1 ±9.3% vs 45.7±12.2%, P<0.001), a higher placenta mean weight (178 ± 8 mg vs 104 ± 8 mg, P<0.001), a higher mean embryo weight (1042 ± 134 mg vs 721±91 mg, P<0.001), and a lower aPTT (58±15 sec vs 94±14 sec, P, <0.001). Micewho were treated with high-dose aspirin also had a lower resorption rate, although not as much as in the low-dose aspirin group (34.2 ± 12.7% vs 45.7 ± 12.2%, P<0.001). CONCLUSION: Aspirin, especially in low dose, has a protective effect against obstetrical complications associated with experimental APLS.  相似文献   
2.
The human lymphokine, leucocyte migration-inhibitory factor (LIF), appears to be a serine esterase and protease by virtue of its susceptibility to the irreversible enzyme inhibitor, phenylmethylsulfonyl fluoride (PMSF), and by the ability of arginine esters and amides to protect LIF against PMSF-induced inactivation. In this paper, three methods are described by which putative substrates for LIF may be investigated. Thus, molecules satisfying the substrate specificities of this lymphokine should (1) protect LIF against inactivation by PMSF, (2) reduce LIF activity in vitro on polymorphonuclear leucocytes, and (3) reduce the esterolytic activity of purified LIF-rich supernatants. The first two reactions were tested by means of the leucocyte migration agarose technique; the third reaction was tested by a sensitive enzyme assay using tritiated tosyl arginine methyl ester as substrate. Guanosine 3',5'-cyclic monophosphoric acid, which is capable of protecting LIF against PMSF-induced inhibition, also inhibited the esterolytic activity of the purified LIF preparation. Four synthetic oligopeptide substrates for trypsin, thombin and plasmin were investigated. Only one, the thrombin- and trypsin-specific benzoyl-phenylalanyl-valyl-agarine-p-nitroanilide, possessed high affinity for the LIF molecule and may therefore prove to be a potent substrate for this lymphokine.  相似文献   
3.
Trauma to the chest can result in cardiac damage, which maybe missed by clinical examination because of associated injuries.Routinely performed non-invasive tests may also be non-diagnostic.Tc-99m pyrophos-phate (PPi) tomography, in this study combinedwith T1-201, is a promising addition to non-invasive evaluation.In three patients with cardiac injury, this technique successfullydetected and localized myocardial necrosis.  相似文献   
4.
Summary. The possibility of alloimmunization in patients receiving protein replacement therapy depends on (at least) three risk factors, which are necessary concomitantly but insufficient alone. The first is the degree of structural difference between the therapeutic protein and the patient’s own endogenous protein, if expressed. Such differences depend on the nature of the disease mutation and the pre‐mutation endogenous protein structure as well as on post‐translational changes and sequence‐engineered alterations in the therapeutic protein. Genetic variations in the recipients’ immune systems comprise the second set of risk determinants for deleterious immune responses. For example, the limited repertoire of MHC class II isomers encoded by a given person’s collection of HLA genes may or may not be able to present a ‘foreign’ peptide(s) produced from the therapeutic protein – following its internalization and proteolytic processing – on the surface of their antigen‐presenting cells (APCs). The third (and least characterized) variable is the presence or absence of immunologic ‘danger signals’ during the display of foreign‐peptide/MHC‐complexes on APCs. A choice between existing therapeutic products or the manufacture of new proteins, which may be less immunogenic in some patients or patient populations, may require prior definition of the first two of these variables. This leads then to the possibility of developing personalized therapies for disorders due to genetic deficiencies in endogenous proteins, such as haemophilia A and B. [Correction made after online publication 11 July 2011: several critical corrections have been made to the abstract].  相似文献   
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Background: Type-1 long-QT syndrome (LQT1) is caused by mutations in the KCNQ1 gene. The purpose of this study was to investigate whether KCNQ1 mutations in highly conserved amino acid residues within the voltage-gated potassium channel family are associated with an increased risk of cardiac events.
Methods and Results: The study population involved 492 LQT1 patients with 54 missense mutations in the transmembrane region of the KCNQ1 channel. The amino acid sequences of the transmembrane region of 38 human voltage-gated potassium channels were aligned. An adjusted Shannon entropy score for each amino acid residue was calculated ranging from 0 (no conservation) to 1.0 (full conservation). Cox analysis was used to identify independent factors associated with the first cardiac event (syncope, aborted cardiac arrest, or death). Patients were subcategorized into tertiles by their adjusted Shannon entropy scores. The lowest tertile (score 0–0.469; n = 146) was used as a reference group; patients with intermediate tertile scores (0.470–0.665; n = 150) had no increased risk of cardiac events (HR = 1.19, P = 0.42) or aborted cardiac arrest/sudden cardiac death (HR = 1.58, P = 0.26), and those with the highest tertile scores (>0.665; n = 196) showed significantly increased risk of cardiac events (HR = 3.32, P <0.001) and aborted cardiac arrest/sudden cardiac death (HR = 2.62, P = 0.04). The increased risk in patients with the highest conservation scores was independent of QTc, gender, age, and beta-blocker therapy.
Conclusions: Mutations in highly conserved amino acid residues in the KCNQ1 gene are associated with a significant risk of cardiac events independent of QTc, gender, and beta-blocker therapy.  相似文献   
8.
Risk Factors for Recurrent Heart Failure . Background: This study was designed to identify risk factors for recurrent heart failure (HF) events in patients with ischemic left ventricular dysfunction enrolled in the Multicenter Automatic Defibrillator Implantation Trial II (MADIT‐II). Methods and Results: The Prentice, Williams, and Peterson (PWP) statistical model was utilized to identify and compare risk factors for 1 or ≥2 HF hospitalizations among 1,218 patients with ischemic left ventricular dysfunction enrolled in the MADIT‐II trial. Risk factors for a first HF hospitalization included treatment with an ICD (HR = 1.31; P = 0.05), New York Heart Association class >II (HR = 1.95; P < 0.001), female gender (HR = 1.38; P = 0.05), atrial fibrillation (HR = 1.90; P = 0.001), QRS >120 ms (HR = 1.41; P = 0.01), diabetes mellitus (HR = 1.51; P = 0.003), heart rate ≥80 (HR = 1.35; P = 0.04), diuretic therapy (HR = 1.82; P < 0.001), and the presence of prerenal azotemia (defined as blood urea nitrogen:creatinine >20; HR = 1.45; P = 0.01). In contrast, prerenal azotemia was the only risk factor that was independently associated with a significant increase in the risk of ≥2 HF hospitalizations (HR = 1.52; P = 0.027). The occurrence of 1 HF event after enrolment was associated with a 2.8‐fold (P < 0.001) increase in the risk of death, whereas after the occurrence of a second event there was a 6.7‐fold (P < 0.001) increase in the risk of subsequent mortality. Conclusions: In MADIT‐II, prerenal azotemia was the only significant and independent risk factor for HF progression after a first event, and recurrent HF was the most powerful predictor of mortality. These findings stress the importance of identifying risk factors for HF progression among patients who receive an ICD for primary prevention. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1217‐1223, November 2010)  相似文献   
9.
A 62-year-old woman was admitted for the evaluation of pedal edema and ascitis. Echocardiography revealed a right atrial (RA) mass invading the interatrial septum and extending into the inferior vena cava (IVC). Contrast enhanced computerized tomography scan excluded extravascular involvement. An organized thrombus was diagnosed by transvenous endomyocardial biopsy. The patient was treated with continuous intravenous heparin, and died soon after from hepatic failure. Postmortem histologic examination revealed a leiomyosarcoma surrounded by a thrombus involving RA, IVC, and hepatic veins. Endomyocardial biopsy played a misleading role that affected patient's management.  相似文献   
10.
Semen analyses of 529 men who consulted our department due to infertility problems, were related to the time period prior to conception, with factors adversely affecting the fertility of the female partner taken into consideration. The statistical method used was Cox's proportional-hazard model of regression. Untransformed, logarithmically transformed and dichotomized semen analysis variables were included in the calculations. The relationship between the following parameters and the probability of conception was examined: sperm count, sperm motility, progressive sperm motility, morphology and sperm motility remaining 24 h after ejaculation. All variables co-varied with the probability of conception; however, the exact type of relationship could not be determined by regression analyses. Cox's model assumes an exponential relationship. Our data suggest that this assumption is not suitable for fertility investigations. Using conventionally defined limiting values for normal and pathological semen quality, statistical analysis yielded significant differences in fertility between both categories for all of the variables considered; in the stepwise regression analysis, however, it could be shown that progressive motility and morphology alone were sufficient to discriminate between normal and pathological semen quality. The results are interpreted as indicating that, as a result of semen analysis, it is possible to predict the individual probability of conception if the exact shape of the relationship can be determined, which, up to now, has not been accomplished.  相似文献   
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