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Abstract: This study analyzes the serum transferrin receptor (sTfR) levels in a series of 230 ex-thalassemics with a follow-up of 1 to 9 years after bone marrow transplantation (BMT) for homozygous β thalassemia. Ex-thalassemics are individuals, cured of homozygous β thalassemia by BMT, who maintain different degrees of iron overload acquired during the pretransplant period. Both in experimental and clinical conditions, sTfR concentrations have been shown to be a quantitative measure of body iron status. This study was carried out to assess whether the level of sTfR may be of help in determining the extent of iron overload in ex-thalassemics. Patients who received the marrow from their HLA-identical sibling donor heterozygous for β thalassemia, namely heterozygous ex-thalassemics, displayed significantly higher levels of sTfR than patients transplanted from their normal sibling donors (normal ex-thalassemics). This finding suggests that increased erythropoiesis, albeit in part ineffective in heterozygous ex-thalassemics, is responsible for the sTfR increment. Both heterozygous and normal ex-thalassemics had significant lower sTfR levels than their heterozygous (p < 0.003) or normal (p < 0.0001) donors, respectively. These differences may be ascribed to the presence of iron overload in ex-thalassemics in comparison to their normal or heterozygous donors who did not present excess of iron in the body. A significant inverse correlation between sTfR and serum ferritin levels (r = –0.54, p < 0.0001) was found when normal ex-thalassemics were considered. In heterozygous ex-thalassemics, the lack of correlation between these two parameters may be explained by the enhanced erythropoietic activity of individuals with thalassemic trait. These results suggest that the level of sTfR may be a useful indicator of iron overload in normal ex-thalassemics.  相似文献   
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Individuals with Down's syndrome (DS), i.e., trisomy 21, over 40 years of age, are likely to develop neuropathological changes characteristic of Alzheimer's disease (AD). The involvement of chromosome 21 both in DS and AD suggests a shared genetic susceptibility to these disorders, but genetic determinants are still undefined. The -48C/T polymorphism in the PSEN1 promoter is a possible candidate, since it has recently been associated with an increased risk of early onset AD. Based on the assumption that the excess of dementia in DS might be a consequence of a different distribution of the -48C/T polymorphism, we investigated the association between DS and this polymorphism in patients with trisomy 21 and controls. Overall, 260 DS patients and 197 controls were recruited at the Department of Neurosciences, Tor Vergata University of Rome. Cases and controls had similar age and gender distribution. High molecular weight DNA was extracted from whole blood samples collected in EDTANa(2) and -48C/T genotypes were determined. Genotype and allele frequencies were compared between cases and controls. Cases were less likely than controls to have the CC genotype ( P = 0.05). A significant difference for allele distribution between DS cases and controls was found, with DS showing a lower frequency of the allele C compared with the control population (OR: 0.57; 95% CI: 0.35-0.91; P = 0.01). No significant interaction of PSEN1 with age, gender, ApoE and -850 TNF-alpha polymorphisms was found. The association found suggests that the -48C/T polymorphism in the PSN1 gene promoter, which is involved in the modulation of amyloid beta load in human AD, is associated with DS. However, the biological role of this polymorphism in DS-related dementia remains unclear and merits further investigation.  相似文献   
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A 43-year-old woman had unilateral exophthalmos caused by primary orbital Ewing sarcoma. Specialized immunohistochemical stains, primarily MIC-2 (CD99), aided in the diagnosis of Ewing sarcoma. Twenty-two months after radiotherapy and multiagent chemotherapy, the patient remained tumor free. To our knowledge, this is the first reported case of orbital Ewing sarcoma to present in an adult beyond the fourth decade of life.  相似文献   
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The interplay existing between immune reconstitution and patient outcome has been extensively demonstrated in allogeneic hematopoietic stem cell transplantation. One of the leading causes of infection-related mortality is the slow recovery of T-cell immunity due to the conditioning regimen and/or age-related thymus damage, poor naïve T-cell output, and restricted T-cell receptor (TCR) repertoires. With the aim of improving posttransplantation immune reconstitution, several immunotherapy approaches have been explored. Donor leukocyte infusions are widely used to accelerate immune recovery, but they carry the risk of provoking graft-versus-host disease. This review will focus on sophisticated strategies of thymus function-recovery, adoptive infusion of donor-derived, allodepleted T cells, T-cell lines/clones specific for life-threatening pathogens, regulatory T cells, and of T cells transduced with suicide genes.  相似文献   
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OBJECTIVE: Impaired diastolic function and left ventricular hypertrophy can occur early in the natural history of essential hypertension. High circulating levels of endogenous ouabain (EO) have been described in essential hypertension and have also been associated with left ventricular hypertrophy. The aim of this study was to investigate whether these cardiac modifications are related to plasma EO levels in the offspring of hypertensive families. METHODS: The study involved 41 subjects with (FAM+) and 45 subjects without (FAM-) a family history of hypertension. Arterial blood pressure, left ventricular geometry and function, and plasma EO levels were measured in each subject. RESULTS: Plasma EO levels were higher in the FAM+ subjects (221.5 +/- 10.95 versus 179.6 +/- 9.58 pmol/l, P = 0.004), and directly correlated with both systolic (r = 0.417, P < 0.0001) and diastolic blood pressure (r = 0.333, P = 0.002). Plasma EO was inversely related to an index of cardiac diastolic function determined as the ratio between the early and late peak flow velocity (r = -0.286, P = 0.012) and isovolumetric relaxation time (IVRT) (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, correlated with the IVRT (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, whereas the other echocardiographic parameters were similar to FAM-. CONCLUSIONS: Among the offspring of families with a positive history of hypertension, circulating EO levels and blood pressure are increased. Plasma EO levels are related to alterations of some indexes of diastolic heart function in these individuals.  相似文献   
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Advances in the allogeneic transplantation for thalassemia   总被引:2,自引:0,他引:2  
Hematopoietic stem cell transplantation (HSCT) remains the only curative option for patients with thalassemia. Current results of transplantation in patients aged less than 17 years from matched related donors offer 80% to 87% probability of cure according to risk classes. Adult thalassemics treated with myeloablative conditioning continue to have inferior results because of their advanced stage of disease. With the introduction of high-resolution tissue typing techniques transplant centres worldwide are able to offer allogeneic HSCT to a much larger cohort of patients who could not benefit from transplantation because of lack of matched family donor. Although limited number of patients treated, results of transplant from unrelated matched donors are comparable to those obtained using sibling donors. Graft failure or rejection remains a significant cause of transplant failure in patients with thalassemia making difficult to perform reduced intensity conditioning regimens. Mixed chimerism is a common phenomenon after transplantation and is a risk factor for rejection. Ex-thalassemics still carry the clinical complications acquired during years of transfusion and chelation therapy. Longer follow-up and management of these complications in ex-thalassemics are essential.  相似文献   
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