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111.
Late adverse reactions to intravascular iodinated contrast media   总被引:1,自引:0,他引:1  
Late adverse reactions to intravascular iodinated contrast media are defined as reactions occurring 1 h to 1 week after contrast medium injection. They have received increasing interest over the past decade, but their prevalence remains uncertain and their pathophysiology is not fully understood. The Contrast Media Safety Committee of the European Society of Urogenital Radiology decided to review the literature and to issue guidelines. An extensive literature search was carried out and summarized in a report. Based on the available information, simple guidelines have been drawn up. The report and guidelines were discussed at the 8th European Symposium on Urogenital Radiology in Genoa. Late adverse reactions after intravascular iodinated contrast medium include symptoms such as nausea, vomiting, headache, itching, skin rash, musculoskeletal pain, and fever. A significant proportion of these reactions is unrelated to the contrast medium; however, allergy-like skin reactions are well-documented side effects of contrast media with an incidence of approximately 2%. Late reactions appear to be commoner after non-ionic dimers. The majority of late skin reactions after contrast medium exposure are probably T-cell-mediated allergic reactions. Patients at increased risk of late skin reactions are those with a history of previous contrast medium reaction and those on interleukin-2 treatment. Most skin reactions are self-limiting and resolve within a week. Management is symptomatic and similar to the management of other drug-induced skin reactions. Electronic Publication  相似文献   
112.
BACKGROUND: N-3 fatty acids (FA) have an important role in brain development and function. However, there is conflicting evidence concerning the relationship between n-3 FA and dementia in older persons. METHODS: In the Invecchiare in Chianti (InCHIANTI) study, we measured plasma FA by gas chromatography in 935 community-dwelling older persons randomly extracted from the population of two towns near Florence, Italy. Cognitive impairment was measured using the Mini-Mental Status Examination. Participants who scored 相似文献   
113.
Hydroxymethyl-glutaryl-CoA-reductase inhibitors (statins) reduce cardiovascular mortality by decreasing cholesterol as well as by non-lipid-related actions. Oxidized low-density lipoproteins (ox-LDL) are pro-atherogenic molecules and potent platelet agonists. CD36 and lectin-like ox-LDL receptor-1 (LOX-1) are specific ox-LDL receptors also expressed in platelets. This study was planned to address whether treatment with atorvastatin 10 mg/day, pravastatin 40 mg/day or simvastatin 20 mg/day could affect platelet CD36 and LOX-1 expression. Twenty-four patients for each treatment were evaluated after 3, 6, and 9 days and at 6 weeks for complete lipid profile (chromogenic), ox-LDL (ELISA), platelet P-selectin (P-sel), CD36, LOX-1 (FACS), and intracellular citrullin recovery (iCit) (HPLC). Data show hyperactivated platelets (P-sel absolute values, percent variation in activated cells, all p < 0.001), and CD36 and LOX-1 overexpression (all p < 0.001) in patients at baseline. P-sel, CD36, and LOX-1 were significantly decreased by atorvastatin and simvastatin (all p < 0.01) and related with iCit increase (r = 0.58, p < 0.001) and platelet-associated ox-LDL (r = 0.51, p < 0.01) at 9 days. Pravastatin reduced LOX-1 and P-sel (p < 0.05) at 6 weeks in relation with decreased LDL and ox-LDL (r = 0.39, p < 0.01 and r = 0.37, p < 0.01, respectively). These data suggest that atorvastatin and simvastatin reduce platelet activity by exposure of CD36 and LOX-1 before significant LDL reduction, whereas pravastatin action is detected later and in relation with LDL and ox-LDL lowering. Rapid and consistent reduction of CD36 and LOX-1 could be considered a direct anti-atherothrombotic mechanism related to the role of ox-LDL in platelet activation, platelet-endothelium interactions, and NO synthase activity.  相似文献   
114.
Over the last few years, much progress has been made in understanding the genetic basis of primary aldosteronism. This has led to the diagnosis of the familial forms and has aided the understanding of the basis of sporadic forms of the disease. Such information can be exploited to improve the therapeutic approaches used not only for patients with primary aldosteronism, but also with other forms of hypertension. Here, we review the genetic and the phenotypic features of the familial forms, the genetic variants that influence the sporadic forms and the structure and regulation of the CYP11B1 and CYP11B2 genes.  相似文献   
115.
Aim of the study: The Consistent Atrial Pacing (CAP) algorithm has been designed to achieve a high percentage of atrial pacing to suppress paroxysmal atrial fibrillation. The aim of our study was to compare the impact of DDDR+CAP versus DDDR pacing on paroxysmal atrial fibrillation recurrences and triggers in patients with Brady-Tachy Syndrome. Methods: 61 patients, 23 M and 38 F, mean age 75±9 y, affected by Brady-Tachy Syndrome, implanted with a DDDR pacemaker, were randomized to DDDR or DDDR+CAP pacing with cross over of pacing modality after 1 month. Results: 78 % of patients in DDDR pacing and 73 % in DDDR+CAP pacing (p=n.s.) were free from symptomatic paroxysmal atrial fibrillation recurrences. During DDDR+CAP pacing, the atrial pacing percentage increased from 77±29 % to 96±7 % (p<0.0001). Automatic mode switch episodes/day were 0.73±1.09 in DDDR and 0.79±1.14 (p=n.s.) in DDDR+CAP. In patients with less than 50 % of atrial pacing during DDDR, automaticmode switch episodes/day decreased during DDDR+CAP from 1.13±1.59 to 0.23±0.32 (p<0.05) and in patients with less than 90 % from 1.23±1.27 to 0.75±1.10 (p<0.001). The number of premature atrial complexes per day decreased during DDDR+CAP from 2665±4468 to 556±704 (p<0.02). Conclusion: CAP algorithm allowed continuous overdrive atrial pacing without major side effects. Triggers of paroxysmal atrial fibrillation induction, such as premature atrial complexes, were critically decreased. Paroxysmal atrial fibrillation episodes were reduced in patients with atrial pacing percentage lower than 90 % during DDDR pacing.  相似文献   
116.
Introduction: Celiac disease (CD) is an immune-mediated disorder associated with gluten exposure in genetically predisposed subjects.

Areas covered: Infectious disease is one of the causes of morbidity and mortality in CD patients. Invasive streptococcus pneumoniae (pneumococcus) is a particularly dangerous morbid condition in both the general population and celiac patients. Pneumococcal vaccination is the most effective means for its prevention.

Expert opinion: In CD, evaluation of spleen function should be useful to select patients who may benefit from vaccination to reduce the risk of pneumococcal disease. Different strategies could be employed: physicians could search for signs of hyposplenism on peripheral blood smear or abdominal ultrasound. However, the best strategy to identify which patients will benefit from pneumococcal vaccination has not yet been defined.  相似文献   

117.
Antibody-mediated inhibition of Plasmodium falciparum parasites in vitro reflects the potential parasite-neutralizing activity of the antibodies in vivo. In this study, immunoglobulins and P. falciparum isolates were collected from children with asymptomatic malaria in Burkina Faso. We demonstrate a significantly lower in vitro growth inhibitory activity against the P. falciparum field isolates by autologous host immunoglobulin compared with that of immunoglobulin from other individuals. To gain further insight to possible mechanisms for the diverse sensitivity observed, analyses of consecutive isolates taken 14 days apart were performed with regard to polymerase chain reaction-based genotyping and sensitivity to growth inhibition in vitro. All the asymptomatic infections were composed of multiple, genotypically distinct parasite clones, and at least one new parasite clone appeared in most of the day 14 isolates compared with the corresponding day 0 isolates. Apparently persisting parasite clones, present in both the day 0 and day 14 isolates from the same person, were also frequently observed. The day 14 isolates were more effectively inhibited by autologous day 14 immunoglobulin than by the corresponding day 0 immunoglobulin in 57% of the cases. However, the frequent presence of persisting parasite clones in asymptomatic children indicates that the parasite may develop a relative resistance to neutralizing immune responses.  相似文献   
118.
Type II fiber loss and reactive oxygen species (ROS)-induced damage are hallmarks of muscle aging. The aim of this study was to analyze whether there exists a relationship between age-dependent changes in cellular antioxidant capacity and type II fiber loss in aged human skeletal muscles. Forty-five male and female subjects ranging in age from 65 to 90 year-old were divided into +40 and -40% type II fiber groups. We measured both total and Mn superoxide dismutase (total and MnSOD), glutathione peroxidase (GSHPx) and catalase (CAT) activities. We also measured the reduced and oxidized forms of glutathione (GSH and GSSG) and lipid peroxide (LPO) levels. Total SOD activity was lower in the -40% type II fiber group than in the +40% group; MnSOD tended to be lower but data are not statistically consistent. Both GSHPx and CAT activities remained unchanged; as did GSH, GSSG and GSH/GSSG ratio. Finally, muscle samples with -40% type II fibers had a significantly higher LPO content compared to those with +40% type II fibers. In summary, a relationship between human skeletal muscle aging, type II fiber loss and ROS reactions seems to exist.  相似文献   
119.
BACKGROUND: Even if diastolic function has been assessed in athletes by analysis of transmitral Doppler flow, no one has studied pulmonary venous flow in this population. The aim of this study was to establish if the physiological adaptations following a prolonged physical training could influence the diastolic function in a professional Olympic male runner group. METHODS: From February to December 1999 we studied 25 athletes (Group I) during the period of maximal training compared with 18 age- and sex-matched healthy sedentary subjects (Group II). We used mono- and bidimensional Echocardiography to assess left ventricular structure and systolic function. The diastolic function was evaluated by Doppler method assessing transmitral and venous pulmonary flow. RESULTS: From the comparison between the two groups, we found great differences in the interventricular septum and the posterior wall thickness; the analysis of the systolic function demonstrated a significant increase in ejection fraction, stroke volume, left ventricular mass, and end diastolic volume in the athletes' population. Fluximetric study showed that ventricular diastolic function is not influenced by hypertrophy: indeed, Doppler evaluation of the transmitral flow showed a bigger velocity of the E wave, similarly, when we assessed pulmonary venous flow, we found faster retrograde Ar wave in group I. CONCLUSIONS: Our data indicate that diastolic function remains normal or improves in some cases after physical training; left ventricular hypertrophy and concentric remodeling do not involve diastolic changes like hypertrophic and hypertensive heart diseases.  相似文献   
120.
Transplantation of genetically modified hematopoietic stem cells (HSCs) has therapeutic potential for a variety of blood genetic disorders. Engraftment of HSCs, however, requires toxic myeloablative treatments, which render this approach questionable for non-life-threatening disorders. A potential alternative is the use of transgenes, which allows positive selection of HSCs in vivo. We used retroviral vectors to express a truncated derivative of the erythropoietin receptor (tEpoR) in murine and human hematopoietic cells. Murine HSCs expressing tEpoR at different levels (1500 to 13,000 receptors/cell) acquire a competitive repopulation capacity in vivo upon transplantation into fully or partially myeloablated co-isogenic mouse recipients. Long-term analysis of transplanted mice showed that expression of tEpoR at paraphysiological levels (approximately 1500 receptors/cell) has no effect on steady-state hematopoiesis and induces no further expansion of transduced cells after the engraftment period. Human cord blood-derived CD34+ stem/progenitor cells transduced with a lentiviral vector expressing tEpoR expand their clonogenic capacity in vitro, and significantly increase their marrow repopulation capacity upon xenotransplantation into sublethally irradiated NOD-SCID mice, with no alteration in their phenotype, survival, and differentiation properties. These data indicate that expression of tEpoR is an effective strategy to promote selective engraftment of genetically modified HSCs upon transplantation in both myeloablative and nonmyeloablative conditions, without the use of toxic drugs for selection.  相似文献   
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