[Show abstract][Hide abstract] ABSTRACT: Objective:
Alterations in microRNA (miRNA) expression have been described in thyroid tumors, suggesting a role for miRNAs in thyroid carcinogenesis. BRAF(V600E) is the most frequently identified genetic alteration in papillary thyroid carcinoma (PTC). We investigated the link between BRAF(V600E) status and the expression of miRNAs in PTC and analyzed the associations of these factors with clinicopathological characteristics.
Design and methods:
Prospective study of patients who underwent thyroid surgery between October 8, 2008 and November 1, 2010. BRAF(V600E) status was determined by mutant allele-specific amplification PCR and direct sequencing of exon 15 of the BRAF gene in 69 PTC tissues and 69 respective paracancerous normal thyroid tissues. Initially, miRNA expression was analyzed in 12 PTC tissues and three associated paracancerous tissues using a miRNA microarray. miRNAs differentially expressed between BRAF(V600E)-positive and -negative PTC tissues were then validated by real-time quantitative PCR on 69 PTC tissues and 69 paracancerous tissues. We also explored the associations between BRAF(V600E) status or differential miRNA expression and clinicopathological characteristics.
The mutation rate of BRAF(V600E) in PTC was 47.8%. Twelve miRNAs were upregulated and six were downregulated in PTC tissues, among which miR-15a, 15a*, 34a*, 34b*, 551b, 873, 876-3p, and 1274a were first identified. miR-21* and 203 were significantly dysregulated (P<0.05) in PTC tissues with BRAF(V600E). Additionally, there were significant associations (P<0.05) between BRAF(V600E) and a higher tumor-node-metastasis staging (III/IV), and between miR-21* over-expression and lymph node metastasis.
We identified two miRNAs that are differentially expressed in PTC tissues with BRAF(V600E) and revealed their associations with clinicopathological features. These findings may lead to the development of a potential diagnostic biomarker or prognostic indicator of PTC.
Preview · Article · Feb 2013 · European Journal of Endocrinology
[Show abstract][Hide abstract] ABSTRACT: Circulating tissue factor positive microparticles (MPTF) were reported in a wide range of diseases with thrombotic tendency. Though D-dimer assay had a high negative predictive value for deep venous thrombosis (DVT) recurrence, there are currently no reliable positive predictors for recurrent DVT. We therefore quantified MPTF in patients with acute recurrent DVT to determine whether MPTF levels could be used to predict recurrent DVT.
Microparticles (MPs) were isolated from plasma of initial DVT patients (n=25), recurrent DVT patients (n=25) and sex- and age-matched healthy individuals (n=25), stained with annexin V, cell-specific monoclonal antibodies (MoAbs) and a MoAb directed against tissue factor (TF), and analyzed by flow cytometry. We also determined the plasma procoagulant activity with a Human TF Chromogenic Activity Assay Kit.
We found total MPTF to be elevated in recurrent DVT patients versus normal individuals (P=0.001). The number of monocyte-derived MPTF in both initial and recurrent DVT was higher than in normal individuals (P<0.01, respectively). The platelet and endothelial cell derived MPTF in recurrent DVT were significantly increased relative to other MPTF (P<0.05), although there was no difference between initial DVT patients and normal individuals. We demonstrated elevated procoagulant activity of platelet-free plasma in DVT patients relative to normal individuals, and a positive correlation with MPTF.
The elevated MPTF could be a potentially predictor for DVT recurrence. Further studies are needed to validate its sensitivity and specificity.
Full-text · Article · Nov 2011 · Thrombosis Research
[Show abstract][Hide abstract] ABSTRACT: Abdominal aortic aneurysms (AAA) are rare in children and are associated with significant morbidity and mortality as in adults. We summarize our experience in the diagnosis and management of AAAs in 6 children at a single institution.
The clinical data of 6 pediatric patients with AAAs treated at our hospital from November 2005 to November 2008 were retrospectively analyzed.
There were 4 males and 2 females with a mean age at diagnosis of 8 years (range, 17 months to 18 years). All patients presented with pulsatile abdominal masses. Color Doppler ultrasonography and computed tomography angiography were the primary diagnostic tools. One patient has a history of tuberous sclerosis, and 1 had Takayasu's arteritis; no risk factors or identifiable causes were found in the other patients. All of the AAAs identified were infrarenal. Surgical reconstruction with aneurysm resection and prosthetic graft placement was performed successfully in all 6 cases. No intraoperative or postoperative complications occurred. Mean follow-up has been 48 months (range, 32 to 69). In 1 patient, recurrence was noted at 3 years postoperatively. The patient's family declined further surgery, and the patient died, likely of rupture of the aneurysm at 41 months postoperatively. All other patients are currently alive and well.
Our experience indicates that good outcomes can be obtained in children with AAAs with prompt and accurate diagnosis and surgical management with artificial grafts.
No preview · Article · Nov 2011 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: As a common disease, the molecular etiology of noninherited vascular anomalies is still poorly understood. Recently, somatic mutations in exon 17 of the endothelial cell tyrosine kinase receptor Tie-2 (encoded by TEK) were identified in 49.1% of patients with common sporadic venous malformation, a subtype of vascular anomalies. We assessed whether such a mutational region also had a role in the Chinese population or in other subtypes of noninherited vascular anomalies (vascular tumors and vascular malformations).
Direct sequencing of polymerase chain reaction (PCR)-amplified DNA, extracted from 139 lesions in 129 individuals with noninherited vascular anomalies (vascular tumors or vascular malformations) and 60 control samples, was used for detecting the mutations in exon 17 of the TEK gene. Mutations were confirmed by allele-specific PCR. Clone sequences were then used for the mutations identified for the first time. We also explored the associations between these mutations and clinical characteristics (gender, onset age, number of lesions, severity, category, and recurrence of the disease) in both vascular tumors and vascular malformations.
Two somatic TEK mutations (Y897C, R915C) were identified in vascular tumors, and seven somatic TEK mutations (Y897H, Y897C, L914F, R915C, S917I, R918C, R918H) were identified in vascular malformations. Among these mutations, R918C (2,752 C > T) and R918H (2,753 G > A) were first identified in noninherited vascular anomalies. Somatic TEK mutations were detected in lesions from 4 of 23 (17.4%) vascular tumors and 35 of 106 (33.0%) vascular malformations, where most mutations were single substitutions in vascular tumors (100%) and vascular malformations (88.6%), while the remainders were double substitutions. In addition to the reported venous malformation, such mutations were identified in some other subtypes of vascular anomalies, including vascular tumors (infantile hemangioma, pyogenic granuloma, and epithelioid hemangioma) and vascular malformations (capillary malformation, arteriovenous malformation, capillary lymphatic malformation, and capillary arteriovenous malformation). By contrast, these mutations were absent from the control tissues or blood. However, mutations showed no association (P > .05) with clinical characteristics in vascular anomalies or either of its two types (vascular tumors or vascular malformations).
Our study revealed that somatic mutations in exon 17 of the TEK gene were more common in noninherited vascular anomalies than previously reported. Furthermore, such substitutions may shed new light on the molecular etiology, diagnosis, and potential therapeutic targets of vascular anomalies.
Preview · Article · Sep 2011 · Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter