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The protein infusion of basic fibroblast growth factor-2 (FGF-2) and platelet derived growth factor-BB (PDGF-BB) have been shown to promote the formation of a stable and functional vascular network in small and large animal models of ischemia. Here, we sought to determine whether a similar effect could be obtained using a gene-therapy-based strategy with nonviral vectors. Rats underwent a surgical procedure to create hindlimb ischemia and were injected with a combination of plasmids that expressed FGF-2 and PDGF-BB. Anatomical and functional parameters of the angiogenesis and arteriogenesis response were evaluated after 4 weeks. The results were compared with rats injected with plasmids that expressed a reporter gene or the extensively studied vascular endothelial growth factor (VEGF165) alone. Treatment with the FGF-2/PDGF-BB combination increased the angiogenesis and arteriogenesis response compared with the empty plasmid, and it was as effective as VEGF165. In terms of safety, the combination allowed the use of a 50% lower individual dose of each plasmid and in addition promoted the formation of more stable vessels than VEGF165. In conclusion, the dual gene transfer of FGF-2 and PDGF-BB using nonviral vectors is safe and effective in promoting the formation of a functional vascular network in a rodent model of hindlimb ischemia. [ABSTRACT FROM AUTHOR]

Postthrombotic syndrome (PTS) may affect 50% of patients with deep venous thrombosis, 5-10% of them may present severe manifestations. The causes for PTS development and severity have not been well established. This study evaluated whether PTS may be associated with the presence, and echogenicity, of the residual vein thrombosis (RVT). We included patients with a history of deep venous thrombosis in the past 58 months. These patients were further evaluated for PTS diagnosis, clinical comorbidities, plasma levels of D-dimer, serum levels of C-reactive protein and for the presence of RVT. Particularly, RVT was detected by ultrasound examination and the residual thrombi echogenicity was determined by grayscale median (GSM). Fifty-six patients were included, of which 41 presented PTS. Mild PTS was detected in 23 patients, moderate PTS in 11 and severe PTS in seven patients. Patients with severe PTS showed higher body mass index, higher abdominal circumference and higher C-reactive protein levels when compared with the other patients (P = 0.007, P = 0.002, P = 0.02, respectively). The ultrasound-generated GSM was significantly lower in patients with severe PTS compared with patients with mild-moderate PTS or no PTS (median = 24, 35 and 41, respectively; P = 0.04). A GSM value less than 25, which was consistent with a hypoechoic RVT, was the best cut-off value to discriminate patients with severe PTS from those with mild or moderate PTS and those without PTS. RVT is a common finding among patients with PTS and the echogenicity of the RVT may impact the severity of PTS.

Unlabelled: Studies evaluating circulating endothelial cells by flow cytometry are faced by a lack of consensus about the best combination of monoclonal antibodies to be used. The rarity of these cells in peripheral blood, which represent 0.01% of mononuclear cells, drastically increases this challenge., Objective: The aim of this study is to suggest some combinations of markers that would safely and properly identify these cells., Methods: Flow cytometry analysis of circulating endothelial cells was performed applying three different panels composed of different combinations of the CD144, CD146, CD31, CD133, CD45 and anti-Vascular endothelial growth factor receptor-2 antibodies., Results: In spite of the rarity of the events, they were detectable and presented similar inter-person numbers of circulating endothelial cells., Conclusion: The combination of markers successfully identified the circulating endothelial cells in healthy individuals, with the use of three different panels confirming the obtained data as reliable., (Copyright © 2015 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.)

Increased levels of inflammatory markers and clotting factors have been related to the pathogenesis and prognosis of venous thromboembolism. In particular, the imbalance between VWF and ADAMTS13 has been described in patients with arterial thrombosis. In this study, 77 patients with previous VTE and 77 matched controls were selected for the evaluation of the inflammatory markers, FVW, ADAMTS 13 and D-dimer. The presences of post-thrombotic syndrome and residual vein obstruction were also assessed in patients. Serum levels of TNF-α and IL-6 were significantly increased in patients compared to controls (median=2.25 vs 1.59 pg/mL, P ≤ 0.001; 1.16 vs 0.98 pg/ml, P=0.013, respectively). Plasma levels and activity of VWF (median=150.25 vs 95.39 U/dL, P ≤ 0.001; 145.26% vs 92.39%, P ≤ 0.001) and ADAMTS 13 (median=1088.84 vs 950.80 ng/mL, P ≤ 0.001; 96.03 vs 83.64%, P ≤ 0.001) were also higher in patients. We further analysed the subgroups of patients with higher risk for VTE recurrence or VTE sequelae, defined as the presence of high D-dimer levels, RVO or PTS. All inflammatory markers were significantly higher in patients with increased D-dimer. The presence of PTS or RVO was not associated with higher inflammatory or coagulation parameters. The increased levels of inflammatory markers and VWF may suggest that there is a persistence of inflammatory activity in patients even at long periods after the VTE episode. In this context, it may be postulated that increased levels of ADAMTS13 could represent a compensatory mechanism against persistently increased levels of VWF. Moreover, increased inflammatory activity was associated with increased D-dimer levels, thus it is possible that this inflammatory activity may also be related to the risk of VTE recurrence., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Introduction: Deep vein thrombosis (DVT) is a multi-causal disease associated with high morbidity and mortality due to complications, and 25% of patients present recurrence within 5 years. The identification of factors involved with DVT can help in the management of patients, prevention of recurrence and in the development of new therapies. The evaluation of plasma components using proteomics potentially provides a window into the individual's state of health. We analyzed the protein profile of plasma samples from 3 DVT patients and compared results to those obtained from 1 sibling and 1 neighbor of each patient. These patients were selected as they presented a personal and family history of spontaneous and recurrent episodes of proximal DVT., Material and Methods: Albumin was removed using Affi-Gel Blue Gel, and the proteins were alkylated, reduced, precipitated and hydrolyzed. The peptides were fractionated by SCX chromatography, the 7 fractions obtained were directed to the ESI Q-TOF Premier mass spectrometer. Protein search was performed using the Mascot engine against the IPI human database., Results: Proteins that were statistically overexpressed in DVT patients included C4-A plasma protease, C1 inter-alpha-trypsin inhibitor, heavy chain H inhibitor and serum amyloid A. Proteins that were statistically reduced in DVT patients included alpha-2-HS-glycoprotein, isoform 2 of inter-alpha-trypsin inhibitor heavy chain H4 and apolipoprotein A-IV., Conclusions: The evaluation of plasma from patients with spontaneous DVT allows the identification of differently expressed proteins when compared to controls; this expression may be of pathological importance for immune and inflammatory processes in DVT., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Scott syndrome is a rare bleeding disorder due to an impaired exposure of phosphatidilserine on the platelet membrane, compromising the platelet procoagulant activity, thrombin generation and, thus, the clot formation. We report a case of a 17-year-old female adolescent with bleeding episodes of unknown cause. She had normal coagulation, but altered platelet aggregation under arteriolar flow, indicating platelet dysfunction. Furthermore, the expression of Annexin V was markedly reduced and the diagnosis of Scott syndrome was established. She was treated with platelet transfusions and demonstrated a clinical improvement. Scott syndrome may be investigated in cases with bleeding history and normal coagulation tests.

Microparticles (MPs) are blebs released from cellular surfaces during activation/apoptosis. They are procoagulant, pro-inflammatory and could contribute to pathogenesis of deep venous thrombosis (DVT). This study compared the number, cellular origin and procoagulant activity of MPs on DVT patients in different clinical situations: at diagnosis (n = 9, 5F/4M; mean age = 41.11), 1-3 years after warfarin withdrawal (n = 10, 7F/3M; mean age = 32.90), associated to antiphospholipid syndrome (APS; n = 11, 9F/2M; mean age = 33.82), or asymptomatic carriers of Factor V Leiden (FVL; n = 7, 7F/0M; mean age = 34.00) vs healthy controls (CTR). The quantification and characterization were performed by flow cytometry using CD235, CD61, CD45, CD31, CD14, CD45, anti-TF and Annexin V. The plasmatic procoagulant activity was investigated by prothrombin fragment 1 + 2 (F1 + 2) determination. The MPs procoagulant activity was analyzed by D-dimer (DD2) and Thrombin Generation Test (TGT) on a healthy pool of plasmas adjusted or not by their number (10,000 MPs). The MPs percentages were not different between the groups, but absolute number was increased in patients 1-3 years after warfarin withdrawal vs CTR (P = 0.02). There was no difference of the MPs cellular origin comparing patients to controls. TGT using 10,000 MPs was lower on these patients (P = 0.01). APS patients showed a reduction of plasmatic procoagulant activity (P = 0.004), but they were under warfarin therapy. DD2 in the presence of MPs, independently of its number, was higher in patients with DVT at diagnosis (P < 0.0001). MPs of patients with spontaneous DVT at diagnosis can promote coagulation activation demonstrated by increased DD2. Even the increased MPs from patients 1-3 years after thrombotic episode generated lower amount of thrombin, they can have a protective effect by activation of Protein C anticoagulant pathway.