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91.
92.

Summary

Severe adverse drug reactions (ADR) of Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) in some patients receiving strontium ranelate have been reported, but the risk factors are unclear. We show that HLA-A*33:03 and B*58:01 are significantly associated with patients who developed SJS/TEN; and provide the first evidence that genetic risk factors are involved in strontium ranelate-associated SJS/TEN.

Introduction

In this study, HLA as a genetic risk factor was assessed among osteoporotic patients prescribed with strontium ranelate that developed severe cutaneous adverse drug reactions (SCARs) compared with those who were tolerant.

Methods

Genomic DNA isolated from peripheral blood mononuclear cells (PBMCs) of patients was HLA typed using sequencing-based typing method to determine their HLA profiles.

Results

Osteoporotic patients who are currently on strontium ranelate were enrolled in the study (n?=?76). Tolerant controls were defined as patients who received strontium ranelate for a minimum of 3 months (range 3 months to 8 years) with no reports of any cutaneous reactions as these reactions usually occur within the first 12 weeks after starting treatment. Retrospective cases of SJS/TEN were also identified (n?=?5). The majority of the accrued samples were of Han Chinese descent: controls (n?=?72) and cases (n?=?4). All cases and controls were genotyped at four HLA genes, namely HLA-A, HLA-B, HLA-C, and HLA-DRB1. In comparing the samples of Han Chinese descent (72 controls and 4 cases), we found significant associations with HLA-A*33:03 (p?=?0.002) and HLA-B*58:01 (p?=?0.023). There was no significant association with any HLA-C or HLA-DRB1 alleles.

Conclusions

This study reveals that the occurrence of SJS/TEN in Han Chinese patients receiving strontium ranelate is HLA associated. This has important clinical implications for understanding the underlying mechanisms for this ADR as well as evaluating the potential role of genetic pre-screening for osteoporotic patients who may be prescribed strontium ranelate.
  相似文献   
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OBJECTIVE: Over a 70-month period, 100 consecutive Mexican mestizo individuals with a clinical marker associated with a primary hypercoagulable state were studied. METHODS: We prospectively assessed: the sticky platelet syndrome (SPS), the activated protein C resistance (aPCR) phenotype, coagulation protein C activity and antigen, coagulation protein S, antithrombin III, plasminogen, IgG and IgM isotypes of antiphospholipid antibodies, homocysteine levels, the factor V gene Leiden, Cambridge, Hong Kong, and Liverpool mutations, the 677 C-->T mutation in the 5,10-methylenetetrahydrofolatereductase (MTHFR), and the G20210A polymorphism in the 3'-untranslated region of the prothrombin gene. RESULTS: Of the 100 consecutive patients prospectively accrued in the study, only 29% were males. In only 6 individuals could we not record any abnormality, whereas in most individuals (81%), two to five co-existing abnormalities were identified. In a multivariate analysis of the association of all these assesments, the only significant association was found between the factor V Leiden mutation and the aPCR phenotype (r = .495; p < 0.001). CONCLUSIONS: These results confirm previous observations on thrombophilia in Mexico underlining that it is a multifactorial disease. They also suggest that the abnormalities detected are not associated to each other.  相似文献   
95.

Aim

This study aims to characterize the phenolic profile and antioxidant capacity of seven monovarietal virgin olive oils (VOOs) and evaluate their in vitro gastrointestinal stability.

Methods

‘Picual’, ‘Blanqueta’, ‘Sevillana’, ‘Habichuelero’, and ‘Chetoui’ olive cultivars were selected for VOO extraction. The oils were subjected to in vitro digestion. The recovery index (RI) of phenolic compounds after each digestion step and the bioaccessibility index (BI) were evaluated. In addition, the antioxidant activity of the bioaccessible fraction (BF) of VOOs was determined by DPPH, ABTS, and ORAC assays, as well as by studying the intracellular reactive oxygen species in Caco-2 cells.

Results

Differences were found in the composition of phenolic compounds in VOOs depending on cultivars. During the digestive process, important losses of phenolic compounds were observed between the buccal and duodenal steps, unlike HTy and Ty, which presented increased recovery due to the hydrolysis of secoiridoid derivatives. Differences in the bioaccessibility of phenolic compounds were found between varieties of VOOs. ‘Sevillana’ VOO had the highest total bioaccessibility (36%), followed by the ‘Picual’ (19%), ‘Chetoui’ (17%), ‘Habichuelero’ (10%), and ‘Blanqueta’ (8%) varieties. The BF of all the varieties of VOO showed similar radical ABTS scavenging capacity, ‘Chetoui’, and ‘Blanqueta’-BF having the highest radical DPPH scavenging capacity, and ‘Habichuelero’ and ‘Picual’-BF showing protective effects against the peroxyl radical measured by ORACFL assay. All VOO-BFs presented decreases in ROS levels in Caco-2 cells.

Conclusions

Our results suggest differences in the bioaccessibility of phenolics from diverse VOO varieties, which could lead to different biological properties. Therefore, this study represents a first step toward the development of novel dietary strategies focusing on the phenolic supplementation of different VOOs to preserve human health.
  相似文献   
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目的构建P^53与反义mdm2 cDNA序列真核表达载体,并探讨其在人黏液表皮样癌高转移细胞株Mc3细胞中的表达。方法应用分子克隆技术,将mdm2 cDNA序列反向插入到含有P^53基因序列pDOR—Neo中的P^53。基因序列下游,构成含有P^53基因与反义mdm2基因融合基因的逆转录病毒表达载体。经酶切分析鉴定后命名为pDOR—Neo—P^53-F mdm2并将重组载体通过脂质体转染Mc3细胞,通过G418筛选转染阳性细胞,并采用Westernblot方法检测P^53蛋白表达。结果酶切鉴定证实重组载体含有P^53与反义mdm2 cDNA片段,实验结果表明:转染后P^53蛋白(1.35&#177;0.14)较对照组P^53蛋白(6.26&#177;0.11)含量显著减低(P〈0.01),转染空载体P^53蛋白(6.24土0.12)与对照组比较无统计学差异(P〉0.05)。结论P^53与反义mdm2基因融合体真核表达载体构建成功,并表达野生型P^53蛋白和封闭mdm2基因,为今后进一步研究打下了基础。  相似文献   
100.
Prevalence of Isolated Systolic Hypertension (ISH) defined as systolic blood pressure greater than 160 mmHg and diastolic blood pressure less than 90 mmHg was studied in a population of 148 patients treated by hemodialysis whose 80 had undergone ambulatory blood pressure (ABP) recording during the interdialytic period. All patients were treated 3 times 4 hours a week. ABP was recorded for 48 hours between two sessions of hemodialysis using a Delmar Avionic Presurometer (PIV). Prevalence of ISH was 12.5%, while that of systolic-diastolic hypertension (SDH) was 15%. Average age at the time of the study was respectively 59 +/- 13 yrs ISH and 49 +/- 11 yrs SDH (p less than 0.01) while that of patients with normal blood pressure (N) was 57 +/- 10 yrs. Mean duration of HD treatment was no different between groups: 5.3 +/- 3.5 yrs ISH, 5.0 +/- 4.2 yrs SDH and 5.0 +/- 4.3 yrs N. Causes of end-stage renal disease were similar in each group. All patients with ISH and SDH and 42% of N pts were receiving antihypertensive treatment at the time of ABP recording. Finally, level of anemia and percentage of patients treated by EPO were similar in each group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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