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741.
Pokushalov E Romanov A Corbucci G Prohorova D Chernyavsky A Larionov P Terekhov I Artyomenko S Kliver E Shirokova N Karaskov A Dib N 《Journal of cardiovascular translational research》2011,4(6):767-778
Most studies have confirmed the beneficial effects of autologous bone marrow mononuclear cell (BMMC) transplantation on angina, myocardial perfusion, regional wall motion, and LV ejection fraction (LVEF). Cardiac resynchronization therapy (CRT) has also shown a beneficial effect in patients with heart failure (HF) and electrical/mechanical dyssynchrony. However, the relative contribution of BMMC and CRT in patients with ischemic HF and electromechanical dyssynchrony has never been investigated. The aim of this study was to evaluate the benefit of combining BMMC transplantation with CRT in patients with severe ischemic HF, left bundle branch block (LBBB), and mechanical dyssynchrony. Patients with ischemic HF, LVEF?35%, LBBB, and mechanical dyssynchrony underwent intramyocardial transplantation of BMMC and CRTD system implantation. This randomized, single-blind, crossover study compared clinical and echocardiographic parameters during two follow-up periods: 6 months of active CRT (BMMC + CRTact) and 6 months of inactive CRT (BMMC + CRTinact). Physical performance was assessed by means of a 6-min walking test. Myocardial perfusion was evaluated by SPECT. Quality of Life (QoL) was assessed through the Minnesota Living with HF Questionnaire (MLwHFQ). Twenty-six patients (64 ± 7 years) were enrolled in the study. The distance covered by the patients during the 6-min walking test significantly increased in the BMMC + CRTinact phase (BMMC therapy only) in comparison with the baseline (269 ± 68 vs 206 ± 51; p?=?0.007) and in the BMMC + CRTact phase (BMMC therapy + CRT) in comparison with the BMMC + CRTinact (378 ± 59 vs 269 ± 68; p?0.001). The summed rest and stress score (SPECT) decreased significantly in the BMMC + CRTact and BMMC + CRTinact phases in comparison with the baseline (p?≤?0.03). Both phases showed equivalent myocardial perfusion in the segments into which BMMC had been injected. QoL score was significantly lower in the BMMC + CRTinact phase than at the baseline (44.1?±?14 vs 64.8?±?19; p?0.001), and in the BMMC + CRTact phase than in the BMMC + CRTinact phase (26.4?±?12 vs 44.1?±?14; p?=?0.004). BMMC and CRT seem to act independently on myocardial perfusion and electromechanical dyssynchrony, respectively. Combining these two complementary therapies can significantly improve LV performance in patients with severe HF and electromechanical dyssynchrony. 相似文献
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Complex genetic, photothermal, and photoacoustic analysis of nanoparticle-plant interactions 总被引:2,自引:0,他引:2
Khodakovskaya MV de Silva K Nedosekin DA Dervishi E Biris AS Shashkov EV Galanzha EI Zharov VP 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(3):1028-1033
Understanding the nature of interactions between engineered nanomaterials and plants is crucial in comprehending the impact of nanotechnology on the environment and agriculture with a focus on toxicity concerns, plant disease treatment, and genetic engineering. To date, little progress has been made in studying nanoparticle-plant interactions at single nanoparticle and genetic levels. Here, we introduce an advanced platform integrating genetic, Raman, photothermal, and photoacoustic methods. Using this approach, we discovered that multiwall carbon nanotubes induce previously unknown changes in gene expression in tomato leaves and roots, particularly, up-regulation of the stress-related genes, including those induced by pathogens and the water-channel LeAqp2 gene. A nano-bubble amplified photothermal/photoacoustic imaging, spectroscopy, and burning technique demonstrated the detection of multiwall carbon nanotubes in roots, leaves, and fruits down to the single nanoparticle and cell level. Thus, our integrated platform allows the study of nanoparticles' impact on plants with higher sensitivity and specificity, compared to existing assays. 相似文献
745.
Ischemic infarcts and hemorrhages are uncommon but dangerous complications of pregnancy. Their etiology is related to physiological changes during pregnancy. The majority of strokes are seen in the third trimester and postpartum and are etiologically related to three conditions: reversible cerebral vasoconstriction syndrome, preeclampsia/eclampsia and cerebral venous thrombosis. The first two conditions are etiologically connected and can lead to ischemic and hemorrhagic events, whereas cerebral sinus thrombosis is mainly related to hypercoagulation and causes venous infarcts and brain hemorrhages. MRI and CT scans are safe to use for diagnosis of stroke in pregnancy, although use of iodine-based contrast may affect thyroid function of the neonate. Management of stroke in pregnancy is specific to cause and depends on management of blood pressure and delivery in preeclampsia/eclampsia, expected management or calcium channel blockers in reversible cerebral vasoconstriction syndrome, and anticoagulation for cerebral sinus thrombosis. 相似文献
746.
Ocheni S Oyekunle A Kröger N Ayuk F Klyuchnikov E Arps S Held K Zabelina T Adjallé R Wolschke C Zander AR Bacher U 《Acta haematologica》2011,125(3):175-178
747.
Sandra Stöppeler Andree Zibert Ramsi Siaj Jens P Hölzen Evgeny Minin Hartmut H.‐J. Schmidt Hans‐Ullrich Spiegel Daniel Palmes 《Liver international》2011,31(5):642-655
Background: The regeneration capacity of cirrhotic livers might be affected by angiotensin‐1 (AT1) receptors located on hepatic stellate cells (HSC). The effect of AT1 receptor blockade on microcirculation, fibrosis and liver regeneration was investigated. Materials and methods: In 112 Lewis rats, cirrhosis was induced by repetitive intraperitoneal injections of CCl4. Six hours, 3, 7 and 14 days after partial hepatectomy or sham operation, rats were sacrificed for analysis. Animals were treated with either vehicle or 5 mg/kg body weight losartan pre‐operatively and once daily after surgery by gavage. Microcirculation and portal vein flow were investigated at 6 h. The degree of cirrhosis was assessed by Azan Heidenhein staining, activation of HSC by desmin staining, apoptosis by ssDNA detection and liver regeneration by Ki‐67 staining. Changes in expression of various genes important for liver regeneration and fibrosis were analysed at 6 h and 3 days. Haemodynamic parameters and liver enzymes were monitored. Results: Losartan treatment increased sinusoidal diameter, sinusoidal blood flow and portal vein flow after partial hepatectomy (P<0.05), but not after sham operation. AT1 receptor blockade resulted in increased apoptosis early after resection. HSC activation was reduced and after 7 days, a significantly lower degree of cirrhosis in resected animals was observed. Losartan increased the proliferation of hepatocytes at late time‐points and of non‐parenchymal cells early after partial hepatectomy (P<0.05). Tumour necrosis factor (TNF)‐α was significantly upregulated at 6 h and stem cell growth factor (SCF) was downregulated at 3 days (P<0.05). Conclusion: Losartan increased hepatic blood flow, reduced HSC activation and liver fibrosis, but interfered with hepatocyte proliferation after partial hepatectomy in cirrhotic livers. 相似文献
748.
Pokushalov E Romanov A Corbucci G Artyomenko S Turov A Shirokova N Karaskov A 《Journal of cardiovascular electrophysiology》2011,22(4):369-375
Ablation of Paroxysmal and Persistent Atrial Fibrillation . Background: The aim of this prospective observational study was to identify responders to ablation through continuous subcutaneous monitoring for 1 year after ablation in patients with paroxysmal atrial fibrillation (PAF) or persistent AF (PersAF). Method: Patients with symptomatic drug refractory AF were enrolled. Real‐time three‐dimensional (3D) left atrium maps were reconstructed by using a nonfluoroscopic navigation system (CARTO, Biosense‐Webster Inc., Diamond Bar, CA, USA). The ipsilateral left and right pulmonary veins (PVs) were encircled in 1 lesion line by circumferential PV isolation. All patients were implanted with Reveal XT (Medtronic Inc.) for continuous AF monitoring and data collected every month during the 12‐month follow‐up. Results: We enrolled 129 patients (56 ± 9 years, 102 males), all of whom were followed‐up for 12 months after the last ablation procedure: 58 (45%) had a history of PersAF. After only 1 ablation procedure, 76 (59%) of the 129 patients were AF‐free at 12‐month: 48 out of 71 (68%) in the PAF group and 28 out of 58 (48%) in the PersAF group. After 1 or more ablation procedures, 94 (73%) of the 129 patients were AF‐free 12 months after the last procedure: 57 out of 71 (80%) in the PAF group and 37 out of 58 (64%) in the PersAF group. Conclusion: Ablation is highly effective in treating AF, as assessed through detailed 1‐year continuous monitoring: success rate is higher in PAF than in PersAF patients. The use of subcutaneous monitors is a valuable means of identifying responders and nonresponders, and can potentially guide antiarrhythmic and antithrombotic therapies. (J Cardiovasc Electrophysiol, Vol. 22, pp. 369‐375) 相似文献
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Ewa Orlewska Ioan Ancuta Branimir Anic Catalin Codrenau Nemanja Damjanov Predrag Djukic Ruxandra Ionescu Lubomir Marinchev Evgeny L. Nasonov Tonu Peets Sonja Praprotnik Rasho Rashkov Jana Skoupa Witold Tlustochowicz Malgorzata Tlustochowicz Matija Tomsic Tiina Veldi Jelena Vojinovic Piotr Wiland 《Medical science monitor》2011,17(4):SR1-SR13