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Ecotoxicology - Potassium sorbate is the potassium salt of sorbic acid, is a widespread and efficient antioxidant that has multiple functions in plants, traditionally associated with the reactions...  相似文献   
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Assessing cytomegalovirus (CMV)-specific cell-mediated immunity (CMI) represents an appealing strategy for identifying transplant recipients at risk of infection. In this study, we compared two gamma interferon-releasing assays (IGRAs), Quantiferon-CMV and CMV enzyme-linked immunosorbent spot (ELISPOT), to determine the ability of each test to predict protective CMV-specific T-cell responses. Two hundred twenty-one Quantiferon-CMV and ELISPOT tests were conducted on 120 adult kidney transplant recipients (KTRs), including 100 CMV-seropositive transplant recipients (R+) and 20 CMV-seronegative transplant recipients of a CMV-positive donor (D+/R). As a control cohort, 39 healthy adult subjects (including 33 CMV-seropositive and 6 CMV-seronegative subjects) were enrolled. CMV IgG serology was used as a reference for both tests. In the CMV-seropositive individuals, the ELISPOT and Quantiferon-CMV assays provided 46% concordance with the serology, 12% discordance, 18% disagreement between ELISPOT or Quantiferon-CMV and the serology, and 24% gray areas when one or both tests resulted in weak positives. None of the CMV-seronegative subjects showed detectable responses in the ELISPOT or the Quantiferon-CMV test. In transplant recipients, both the ELISPOT and Quantiferon-CMV assays positively correlated with each other and negatively correlated with CMV DNAemia in a significant way (P < 0.05). During the antiviral prophylaxis, all 20 D+/R KTRs we examined displayed undetectable Quantiferon-CMV and ELISPOT results, and there was no evidence of CMV seroconversion. The receiving operator curve (ROC) statistical analysis revealed similar specificities and sensitivities in predicting detectable viremia (areas under the curve [AUC], 0.66 and 0.62 for Quantiferon-CMV and ELISPOT, respectively). ELISPOT and Quantiferon-CMV values of >150 spots/200,000 peripheral blood mononuclear cells (PBMCs) and >1 to 6 IU gamma interferon (IFN-γ) were associated with protection from CMV infection (odds ratios [OR], 5 and 8.75, respectively). In transplant recipients, the two tests displayed similar abilities for predicting CMV infection. Both the ELISPOT and Quantiferon-CMV assays require several ameliorations to avoid false-negative results.  相似文献   
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BackgroundIn patients with phenylketonuria, stability of blood phenylalanine and tyrosine concentrations might influence brain chemistry and therefore patient outcome. This study prospectively investigated the effects of tetrahydrobiopterin (BH4), as a chaperone of phenylalanine hydroxylase on diurnal and day-to-day variations of blood phenylalanine and tyrosine concentrations.MethodsBlood phenylalanine and tyrosine were measured in dried blood spots (DBS) four times daily for 2 days (fasting, before lunch, before dinner, evening) and once daily (fasting) for 6 days in a randomized cross-over design with a period with BH4 and a period without BH4. The sequence was randomized. Eleven proven BH4 responsive PKU patients participated, 5 of them used protein substitutes during BH4 treatment. Natural protein intake and protein substitute dosing was adjusted during the period without BH4 in order to keep DBS phenylalanine levels within target range. Patients filled out a 3-day food diary during both study periods. Variations of DBS phenylalanine and Tyr were expressed in standard deviations (SD) and coefficient of variation (CV).ResultsBH4 treatment did not significantly influence day-to-day phenylalanine and tyrosine variations nor diurnal phenylalanine variations, but decreased diurnal tyrosine variations (median SD 17.6 μmol/l, median CV 21.3%, p = 0.01) compared to diet only (median SD 34.2 μmol/l, median CV 43.2%). Consequently, during BH4 treatment diurnal phenylalanine/tyrosine ratio variation was smaller, while fasting tyrosine levels tended to be higher.ConclusionBH4 did not impact phenylalanine variation but decreased diurnal tyrosine and phenylalanine/tyrosine ratio variations, possibly explained by less use of protein substitute and increased tyrosine synthesis.  相似文献   
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Late evolution of peripheral arterial disease consists in the apparition of critical limb ischemia. Surgical treatments allow to treat these patients during long time; however, in most patients, especially the diabetic ones, there a very few options and the clinical evolution is rapidly dramatic. For these reasons, the critical limb ischemia is one of the first diseases treated by genic or cellular therapies aiming to improve blood flow perfusion in the lower-limbs. In this short review, we describe the main clinical trials of genic therapy; most of them have been abandoned because serious side effects, modest effects and major risks. Different types of stem cells are now used for cell therapy: endothelial progenitor cells, early or late, activated or not, mesenchymal stem cells, embryonic stem cells and human induced pluripotent stem cells. Problems of characterization are described and the results of the most important clinical trials are reported.  相似文献   
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BACKGROUND AND OBJECTIVES: We evaluated the technical and clinical results of implantation of the Atlas stent, the hospital stay, and the short and long-term clinical and angiographic outcome. PATIENTS AND METHOD: The study included 169 patients (60.1 10.8 year-old), 60.3% of which had acute coronary syndromes and complex lesions. Immediate success was achieved in 98% of cases. The clinical follow-up in 85.7% of the patients at 14.3 6.8 months, revealed that 89% remained free of adverse events and most (94.4%) were functional class I of the CCS. Angiographic follow-up at 8.4 4.1 months of 40.9% of the cases revealed restenosis in 27.9%. There were 2 cases of subacute thrombosis. CONCLUSIONS: The application of the Atlas stent in patients with a diverse clinical spectrum demonstrated good immediate and long term results, with a rate of restenosis similar to that of other stents available on the market.  相似文献   
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Background

The aim of this study was to investigate the impact of the introduction of a Patient Blood Management (PBM) programme in elective orthopaedic surgery on immediate pre-operative anaemia, red blood cell (RBC) mass loss, and transfusion.

Materials and methods

Orthopaedic operations (hip, n=3,062; knee, n=2,953; and spine, n=2,856) performed between 2008 and 2011 were analysed. Period 1 (2008), was before the introduction of the PBM programme and period 2 (2009 to 2011) the time after its introduction. Immediate pre-operative anaemia, RBC mass loss, and transfusion rates in the two periods were compared.

Results

In hip surgery, the percentage of patients with immediate pre-operative anaemia decreased from 17.6% to 12.9% (p<0.001) and RBC mass loss was unchanged, being 626±434 vs 635±450 mL (p=0.974). Transfusion rate was significantly reduced from 21.8% to 15.7% (p<0.001). The number of RBC units transfused remained unchanged (p=0.761). In knee surgery the prevalence of immediate pre-operative anaemia decreased from 15.5% to 7.8% (p<0.001) and RBC mass loss reduced from 573±355 to 476±365 mL (p<0.001). The transfusion rate dropped from 19.3% to 4.9% (p<0.001). RBC transfusions decreased from 0.53±1.27 to 0.16±0.90 units (p<0.001). In spine surgery the prevalence of immediate pre-operative anaemia remained unchanged (p=0.113), RBC mass loss dropped from 551±421 to 404±337 mL (p<0.001), the transfusion rate was reduced from 18.6 to 8.6% (p<0.001) and RBC transfusions decreased from 0.66±1.80 to 0.22±0.89 units (p=0.008).

Discussion

Detection and treatment of pre-operative anaemia, meticulous surgical technique, optimal surgical blood-saving techniques, and standardised transfusion triggers in the context of PBM programme resulted in a lower incidence of immediate pre-operative anaemia, reduction in RBC mass loss, and a lower transfusion rate.  相似文献   
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