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21.

Background

Established heart failure in thalassaemia major has a poor prognosis and optimal management remains unclear.

Methods

A 1 year prospective study comparing deferoxamine (DFO) monotherapy or when combined with deferiprone (DFP) for patients with left ventricular ejection fraction (LVEF) <56% was conducted by the Thalassemia Clinical Research Network (TCRN). All patients received DFO at 50–60 mg/kg 12–24 hr/day sc or iv 7 times weekly, combined with either DFP 75 at mg/kg/day (combination arm) or placebo (DFO monotherapy arm). The primary endpoint was the change in LVEF by CMR.

Results

Improvement in LVEF was significant in both study arms at 6 and 12 months (p = 0.04), normalizing ventricular function in 9/16 evaluable patients. With combination therapy, the LVEF increased from 49.9% to 55.2% (+5.3% p = 0.04; n = 10) at 6 months and to 58.3% at 12 months (+8.4% p = 0.04; n = 7). With DFO monotherapy, the LVEF increased from 52.8% to 55.7% (+2.9% p = 0.04; n = 6) at 6 months and to 56.9% at 12 months (+4.1% p = 0.04; n = 4). The LVEF trend did not reach statistical difference between study arms (p = 0.89). In 2 patients on DFO monotherapy during the study and in 1 patient on combined therapy during follow up, heart failure deteriorated fatally. The study was originally powered for 86 participants to determine a 5% difference in LVEF improvement between treatments. The study was prematurely terminated due to slow recruitment and with the achieved sample size of 20 patients there was 80% power to detect an 8.6% difference in EF, which was not demonstrated. Myocardial T2* improved in both arms (combination +1.9 ± 1.6 ms p = 0.04; and DFO monotherapy +1.9 ± 1.4 ms p = 0.04), but with no significant difference between treatments (p = 0.65). Liver iron (p = 0.03) and ferritin (p < 0.001) both decreased significantly in only the combination group.

Conclusions

Both treatments significantly improved LVEF and myocardial T2*. Although this is the largest and only randomized study in patients with LV decompensation, further prospective evaluation is needed to identify optimal chelation management in these high-risk patients.  相似文献   
22.
Behçet’s disease (BD) is a multisystemic disease of unknown aetiology characterized by chronic relapsing oral aphthous lesions, genital ulcers, uveitis, and vasculopathy of both arteries and veins of all sizes. We present the case of a female patient, with BD on oral contraceptive pills, who sustained deep venous thrombosis of the long saphenous vein. The patient was found to be a carrier of a homozygous mutation of the prothrombin (factor II) G20210A gene. Our case suggests that a thrombophilia work-up may be warranted in BD patients, especially young women before they are prescribed oral contraceptives.  相似文献   
23.
Ankylosing spondylitis (AS) is a chronic inflammatory disease, characterized by axial arthritis in which the genetic-environmental factors seem to be involved in the pathogenesis of the disease. This study was performed to investigate the role of polymorphisms of the programmed cell death 1 (PDCD1) gene on susceptibility to AS. In this study, 161 Iranian patients with AS and 208 normal controls were enrolled; two single-nucleotide polymorphisms (SNPs) of the PDCD1 gene PD-1.3 (G, A) in nucleotide position +7146 of intron 4 and PD-1.9 (C, T) in nucleotide +7625 of exon 5 were studied. Analysis of PD-1.3 revealed that 82% of patients and 79% of controls had GG genotype, while GA and AA genotypes were detected in 17% and 0.6% of patients, respectively, and 20% and 1.4% of controls, respectively. Moreover, the genotype CC (PD-1.9) was present in 92% of patients and 97% of controls. Although these differences were not statistically significant between patients and controls, comparisons of genotypes frequencies in the AS patients, based on human leukocyte antigen (HLA)-B27, revealed that all patients who had CT genotype (PD-1.9) were HLA-B27 positive, whereas 30% of patients with CC genotype were HLA-B27 negative. There was no evidence of association for PDCD1 SNPs with AS in our study, but CT genotype (PD-1.9) seems to be associated with HLA-B27 positivity in the patients with AS.  相似文献   
24.

Objective

To investigate the effect of a resin infiltrant on the surface microhardness and roughness of healthy enamel and, as a subsidiary aim, to compare it with a fissure sealant.

Materials and methods

Twenty freshly extracted premolars were used. Sound enamel surfaces were treated with a resin infiltrant (Icon) or fissure sealant (Seal-Rite). The average roughness (Ra, μm) of the specimens was measured with a profilometer (Surtronic 10 Tylor Hobson). Surface hardness was determined by utilizing Vicker’s surface hardness (VHN) with a Micromet II Microhardness tester. Each specimen acted as its own control. Data were analyzed with 2-way analysis of variance (ANOVA), and mean values were compared with independent t-test. All analyses were performed with the SPSS program version 16 (USA). Differences with a P-value of ⩽0.05 were considered statistically significant.

Results

Comparison of enamel surfaces before and after application of resin infiltrant revealed no significant differences in surface hardness; however, enamel surfaces treated by infiltrant showed significantly higher VHN (244.0 ± 79.8) values than those treated with fissure sealant (37.5 ± 14.2). Surface roughness did not differ before and after application of either material to sound enamel. Enamel surfaces treated with fissure sealant (5.3 ± 1.4) were significantly smoother than those treated with infiltrant (6.9 ± 2.0).

Conclusion

Within the limitations of the study, the results showed that enamels treated with the resin infiltrant showed approximately the same microhardness and surface roughness as sound enamel, indicating that this material might be suitable for the treatment of enamel subsurface lesions.  相似文献   
25.
26.
Beta-thalassemia intermedia (TI) is associated with a variety of serious clinical complications that require proactive and comprehensive management. These include skeletal deformities and osteopenia, compensatory extramedullary hematopoiesis and tumor formation, progressive splenomegaly, a hypercoagulable state resulting in thromboembolic events and pulmonary hypertension, and increased gastrointestinal iron absorption that often results in nontransfusional iron overload and liver damage. Although TI is generally considered a non-transfusion-dependent thalassemia, transfusion therapy may be an important part of the comprehensive management of this disease. This review describes the current state of the art for medical management of TI, with particular focus on the roles of splenectomy, transfusion, and iron chelation therapy.  相似文献   
27.
beta-Thalassemia (thal), the most common genetic disorder in Egypt, is a major health problem with an estimated carrier rate of 9-10%. This study, aimed at describing the beta-globin gene mutations in the Suez Canal area, an important Egyptian region, to provide a foundation for a disease control program. We studied 44 beta-thalassemic patients (and their relatives) from 35 families living in this region. The commonest mutations were genetically diagnosed using naturally or amplified created restriction sites. Less frequent mutations were characterized by denaturing gradient gel electrophoresis (DGGE) and direct sequencing. Twelve different mutations were identified in 51 unrelated chromosomes. The three most frequent mutations were IVS-I-110 (G-->A), IVS-I-1 (G-->A) and IVS-I-6 (T-->C). The spectrum of rarer mutations was heterogeneous and differed from that reported in other areas of Egypt. We also identified the first homozygous case of a rare mutation, codon 24 (-G; +CAC), displaying a thalassemia major phenotype. Parental consanguinity was high (60.6%) with 35.7% of the compound heterozygous patients having consanguineous parents. These data provide insights for the distribution of beta-thal alleles in this region, and could be used as a basis for genetic counseling and prenatal diagnosis.  相似文献   
28.
A prospective study was carried out to compare the fertilizing capability and pregnancy outcome following intracytoplasmic sperm injection (ICSI) using spermatozoa obtained from ejaculates, or surgically from epididymis or seminiferous tubules. A total of 77 ICSI cycles (one per patient) was included. In all, 28 patients had severe oligoasthenoteratozoospermia, 19 patients had obstructive azoospermia and 30 patients had non-obstructive azoospermia. The main outcome measures were fertilization rate per injected metaphase II oocyte and the clinical pregnancy rate per embryo transferred back to the female recipients. In patients with severe oligoasthenoteratozoospermia, the fertilization and pregnancy rates were 79 and 25 %. In patients with obstructive azoospermia, for whom epididymal spermatozoa were used, these were 75 and 28%, and in the non-obstructive group for which testicular spermatozoa were used for injection, they were 69 and 21% respectively. These rates were not significantly different in the three groups (P = 0.85 and P = 0.14 respectively), suggesting that spermatozoa from the ejaculates and epididymal or testicular biopsies are able to fertilize equally by using ICSI. Live birth per embryo transfer was significantly reduced in patients with non-obstructive azoospermia compared to the other two groups. The high abortion rate (50%) in the group in which testicular spermatozoa were used raises doubts about the developmental competence of such embryos.   相似文献   
29.
In order to understand the mechanism of unresponsiveness towards Mycobacterium leprae antigens in leprosy, we evaluated the role of M. leprae sonicate antigens in regulating the expression of the costimulatory molecules B7-1, CD28, intercellular adhesion molecule-1 (ICAM-1), LFA-1α, LFA-1β and Mac-1 on the lymphocytes of both leprosy patients and healthy subjects. It was observed that the expression of B7-1 and CD28 was significantly decreased but the levels of ICAM-1 and LFA-1α were increased in patients with untreated borderline leprosy (BL)/lepromatous leprosy (LL) disease. No remarkable change was noticed in the case of borderline tuberculoid (BT) leprosy or treated BL/LL patients. Further, a striking finding was that lymphocytes from healthy subjects cultured with a particularly high dose of M. leprae sonicate antigens down-regulated the expression of B7-1 and CD28 molecules, but up-regulated the display of ICAM-1 and LFA-1α. Furthermore, proliferation induced by M. leprae sonicate was inhibited only by anti-B7-1 antibody. Mycobacterium leprae antigen-induced suppression of the proliferation of lymphocytes of healthy volunteers and LL patients was reversed by culturing the lymphocytes with purified protein derivative (PPD). It may be concluded from the findings in this study that down regulation of B7-1 and CD28 in BL/LL leprosy patients may be responsible for a defective T cell signalling by the B7-1/CD28 pathway caused by M. leprae antigens. This may lead to clonal inactivation of M. leprae-reactive T cells, consequently the bacilli grow without restriction in macrophages.  相似文献   
30.
Acinar cell carcinoma (ACC) is a rare pancreatic malignancy with distinctive clinical, molecular, and morphological features. The long-term survival of ACC patients is substantially superior to that of pancreatic adenocarcinoma patients. As there are no significant patient series about ACCs, our understanding of this illness is mainly based on case reports and limited patient series. Surgical resection is the treatment of choice for patients with the disease restricted to one organ; however, with recent breakthroughs in precision medicine, medicines targeting the one-of-a-kind molecular profile of ACC are on the horizon. There are no standard treatment protocols available for people in which a total surgical resection to cure the condition is not possible. As a result of shared genetic alterations, ACCs are chemosensitive to agents with activity against pancreatic adenocarcinomas and colorectal carcinomas. The role of neoadjuvant or adjuvant chemoradiotherapy has not been established. This article aims to do a comprehensive literature study and present the most recent information on acinar cell cancer.  相似文献   
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