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81.
OBJECTIVES: The purpose of this study was to evaluate the value of platelet reactivity (PR) in predicting the response to treatment and outcome in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention assisted by glycoprotein (GP) IIb/IIIa inhibition. BACKGROUND: There is limited prognostic information on the role of spontaneous or drug-modulated PR in STEMI patients. METHODS: The PR was measured with Platelet Function Analyzer (PFA)-100 and light transmission aggregometry (LTA) using adenosine diphosphate as agonist in 70 consecutive STEMI patients at entry (PR-T0), 10 min after GP IIb/IIIa bolus (PR-T1), and discharge (PR-T2) and in 30 stable angina (SA) patients (PR-SA). Complete platelet inhibition (CPI) was based on closure time >300 s by PFA-100 and percentage inhibition of platelet aggregation >95% by LTA. Clinical, electrocardiographic, and angiographic responses to treatment during 1-year follow-up were collected. RESULTS: According to both techniques, PR-T0 was higher than: 1) PR-T2 and PR-SA; 2) in those without CPI at T1; and 3) in patients with final Thrombolysis In Myocardial Infarction (TIMI) flow grade <3. The PR-T0 assessed with PFA-100 correlated with: 1) corrected TIMI frame count (r = -0.6, p < 0.001); 2) ST-segment resolution (r = 45, p < 0.001); and 3) creatine kinase-MB (r = -0.47, p < 0.001). At 1 year, patients with high PR-T0 showed an adjusted 5- to 11-fold increase in the risk of death, reinfarction, and target vessel revascularization (hazard ratio [HR] 11, 95% confidence interval [CI] 1.5 to 78 [p = 0.02] in PFA-100; HR 5.2, 95% CI 1.1 to 23 [p = 0.03] in LTA). CONCLUSIONS: The PR at entry affects response to GP IIb/IIIa inhibition, mechanical treatment, and long-term outcome in STEMI patients undergoing primary intervention.  相似文献   
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The loss of sensitization over time, the involvement of a different pathogenetic mechanism and the poor sensitivity of diagnostic tests have been included among the causes of a non IgE-mediated anaphylaxis triggered by an insect sting. To provide further insight into this topic we describe the case of a patient suffering from urticaria pigmentosa, anaphylactic shock due to a Vespid sting and monosensitive to Polistes dominulus venom, who was previous diagnosed with non-IgE mediated insect sting anaphylaxis in subjects with urticaria pigmentosa. Therefore ultra-rush specific immunotherapy using an acqueous Polistes dominulus venom extract was performed over two mornings until a total dose of 100mcg was reached without any side effects. Presently the patient is undergoing maintenance therapy with a depot Polistes dominulus venom extract at 4-weekly intervals and is free of side effects. In conclusion, despite the high cross-reactivity among the venoms of the various species of Polistes, recent evidence of a selective specificity unique to European Polistes allergens raises the problem of the need to make the American Polistes venom as well as that of Polistes dominulus (a very common insect in Europe) available both for diagnostic and therapeutic purposes. Besides the fact that the presence of urticaria pigmentosa alone could have explained the anaphylactic reaction to the aspecific stimulation triggered by the venom, this case history also demonstrates that omitting to perform skin tests for Polistes dominulus venom would have led to the same misdiagnosis of non IgE-mediated anaphylaxis and served only to further delay commencing specific immunotherapy.  相似文献   
83.
Six patients showing at coronary angiography normal coronary arteries during dyastole, but a segmental constriction of the left anterior descending artery during systole, were studied. Four of these patients in which the degree of systolic artery narrowing was more evident had typical angina and positive stress test. In two of these cases, a probable idiopathic cardiac hypertrophy was present. The pathogenetic significance of the angiographic findings are discussed, on the basis of common knowledge of coronary physiology and of pathophysiology of angina with normal coronary arteries.  相似文献   
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We conducted a retrospective analysis of all allogeneic stem cell transplantation (ASCT) patients started on extracorporeal photopheresis (ECP) for the management of steroid-dependent (SD) or steroid-refractory (SR) cutaneous chronic graft-versus-host disease (cGVHD) following ASCT during a 36-month period (9/98-8/01). Only SD or SR patients who were treated by ECP after day 100 and who received at least 4 weeks of ECP were considered evaluable for this analysis. Out of 64 ASCT patients reviewed, 32 patients met the inclusion criteria. All 32 patients had been previously treated with systemic corticosteroids with 11 (34%) being SR and 21 (66%) SD. Cutaneous cGVHD was extensive in 28 patients (88%) and was accompanied by visceral (hepatic, gastrointestinal) cGVHD in 23 patients (72%). The 32 evaluated patients had received a median of three prior therapies before ECP, most commonly systemic corticosteroids, tacrolimus, and mycophenolate mofetil. Patients received a median of 36 ECP sessions (range 12-98) over a median of 5.3 months (range 1-28), with a median of six sessions per month. The complete response (CR) rate was 22% (n=7) and the partial response rate was 34% (n=11). In all, 28 patients were on systemic corticosteroid therapy at ECP initiation and 18 patients achieved 50% dose reduction while on ECP, yielding a 64% steroid-sparing response rate. Of seven CRs, five are ongoing. A total of 11 (34%) patients have died after ECP, with all cases due to visceral cGVHD or cGVHD-related infectious complications. All 21 surviving patients remain on at least some immunosuppressive cGVHD therapy (including ECP in eight). Overall, ECP displays a substantial response rate and, in particular, steroid-sparing activity in SR/SD extensive cutaneous cGVHD. However, most patients continue to require at least some chronic therapy and cGVHD-related morbidity and mortality remain high.  相似文献   
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Endothelial dysfunction occurs in conduit and cerebral resistance arteries with advancing age. Lifelong caloric restriction (CR) can prevent the onset of age-related dysfunction in many tissues, but its effects on cerebral resistance artery function, as compared with conduit artery function, have not been determined. We measured endothelium-dependent dilation (EDD) in the carotid artery and middle cerebral artery (MCA) from young (5–7 months), old ad libitum fed (AL, 29–32 months), and old lifelong CR (CR, 40 % CR, 29–32 months) B6D2F1 mice. Compared with young, EDD for old AL was 24 % lower in the carotid and 47 % lower in the MCA (p < 0.05). For old CR, EDD was not different from young in the carotid artery (p > 0.05), but was 25 % lower than young in the MCA (p < 0.05). EDD was not different between groups after NO synthase inhibition with Nω-nitro-l-arginine methyl ester in the carotid artery or MCA. Superoxide production by the carotid artery and MCA was greater in old AL compared with young and old CR (p < 0.05). In the carotid, incubation with the superoxide scavenger TEMPOL improved EDD for old AL (p > 0.05), with no effect in young or old CR (p > 0.05). In the MCA, incubation with TEMPOL or the NADPH oxidase inhibitor apocynin augmented EDD in old AL (p < 0.05), but reduced EDD in young and old CR (p < 0.05). Thus, age-related endothelial dysfunction is prevented by lifelong CR completely in conduit arteries, but only partially in cerebral resistance arteries. These benefits of lifelong CR on EDD result from lower oxidative stress and greater NO bioavailability.  相似文献   
89.
Clinical Rheumatology - Chronic anterior uveitis is the most frequent among extra-articular manifestations of juvenile idiopathic arthritis (JIA) and a relevant cause of ocular morbidity in...  相似文献   
90.
G-CSF administration after high-dose chemotherapy and autologous stem cell transplantation (ASCT) has been shown to expedite neutrophil recovery. Several studies comparing filgrastim and pegfilgrastim in the post-ASCT setting concluded that the two are at least equally effective. Lipegfilgrastim (LIP) is a new long-acting, once-per-cycle G-CSF. This multicentric, prospective study aimed to describe the use of LIP in multiple myeloma patients receiving high-dose melphalan and autologous stem cell transplantation (ASCT) and compare LIP with historic controls of patients who received short-acting agent (filgrastim [FIL]). Overall, 125 patients with a median age of 60 years received G-CSF after ASCT (80 patients LIP on day 1 post-ASCT and 45 patients FIL on day 5 post-ASCT). The median duration of grade 4 neutropenia (absolute neutrophil count [ANC] < 0.5 × 10 [9]/L) was 5 days in both LIP and FIL groups, whereas the median number of days to reach ANC ≥ 0.5 × 10 [9]/L was 10% lower in the LIP than in the FIL group (10 vs 11 days), respectively. Male sex was significantly associated with a faster ANC ≥ 0.5 × 10 [9] L response (p = 0.015). The incidence of FN was significantly lower in the LIP than in the FIL group (29% vs 49%, respectively, p = 0.024). The days to discharge after ASCT infusion were greater in patients with FN (p < 0.001). The study indicates that LIP had a shorter time to ANC recovery and is more effective than FIL for the prevention of FN in the ASCT setting.  相似文献   
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