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This retrospective study aimed to determine the superior vena cava (SVC) and left innominate vein (INV) normative cross-sectional area in children noninvasively using age as a predictor and also to compare the correlation of the area measured with the diameter on multidetector computed tomography (MDCT). Analysis of the SVC-INV cross-sectional area was performed for 73 consecutive patients. The cross-sectional area of the SVC-INV was manually estimated. A regression analysis was performed for the cross-sectional area and age separately, and regression equations were compared. One-way analysis of variance (ANOVA) was performed to evaluate significant differences in the area means according to age groups. Regression analysis showed that age can be a predictor for the area of the SVC (50.6 mm2 + 1.01 × age), te INV (48.3 mm2 + 0.93 × age), and the left SVC-INV junction (47.2 mm2 + 0.92 × age), with respective R 2 values of 93, 88 and 94 %. The comparative evaluation of the cross-sectional area and the diameter measurement of SVC showed that the cross-sectional area was more closely associated with the increasing age of the cohort (R 2 of 68 vs. 61 %) than the measured diameter. For a cohort of patients without congenital or acquired heart disease, MDCT can be used as a complementary test for a normative cross-sectional normogram area database of SVC-INV using age as a predictor.  相似文献   
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Medicinal plants have been traditionally used for treating liver diseases since centuries. Several leads from plant sources have been found as potential hepatoprotective agents with diverse chemical structures. Although, a big list of hepatoprotective phytomolecules was reported in the scientific literature, only a few were potent against various types of liver damages. Of which, silymarin, andrographolide, neoandrographolide, curcumin, picroside, kutkoside, phyllanthin, hypophyllanthin, and glycyrrhizin have largely attracted the scientific community. This review focuses discussion on the chemistry, biological activity, mode of action, toxicity, and future prospects of these leads.  相似文献   
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Introduction: Pulmonary vein (PV) isolation by catheter ablation is an increasingly used strategy to treat atrial fibrillation (AF). Complication rates from AF ablation reported in different case series vary widely. We conducted a retrospective analysis of 641 consecutive ablation procedures to assess complication rates, temporal trends, and clinical predictors of adverse outcomes.
Methods: All patients (n = 517) undergoing catheter ablation for AF at Johns Hopkins Hospital between February, 2001 and June, 2007 were prospectively enrolled in a database. Data from 641 consecutive procedures were analyzed and complications considered if they occurred within 30 days of ablation. Major complications were defined as those that required intervention, resulted in long-term disability, or prolonged hospitalization.
Results: Thirty-two major complications occurred in 641 procedures (5%). Among the patients with major complications, seven had cerebrovascular accident (CVA), eight had tamponade, one had PV occlusion with hemoptysis, and 11 had vascular injury requiring surgical repair and/or transfusion. No periprocedural deaths occurred, and no instances of esophageal injury were seen. Complication rates were higher during the first 100 cases (9.0%) than during the subsequent 541 (4.3%). Major adverse clinical events were associated with age > 70 years (P = 0.007; odds ratio 3.7, 95% confidence interval 1.4–9.6) and female gender (P = 0.014; odds ratio 3.0, 95% confidence interval 1.3–7.2). No other clinical or procedural predictors of complication were identified.
Conclusions: Complication rates from AF ablation remain significant, despite improved techniques and increased awareness of procedural risks. Both advanced age and female gender predict major adverse events, suggesting careful consideration of the risk/benefit profile in these patients prior to ablation.  相似文献   
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Neuroinflammation plays a significant role in various chronic and acute pathological conditions of the central nervous system. In the Indian system of medicine, Pluchea lanceolata is used to treat the neurological disorders. We investigated the effect of major pentacyclic triterpene and its naturally occurring acetate derivative isolated from P. lanceolata on lipopolysaccharide (LPS)-stimulated neuroinflammatory condition associated to inflammatory cytokine production in rat astrocytoma cell line (C6). The log concentration dependence of Pluchea bioactive taraxasterol (Tx) significantly (p?<?0.05) attenuates the release of pro-inflammatory cytokines, such as TNF-α, IFN-γ, and IL-6, while its in situ produced acetyl derivative, i.e., taraxasterol acetate (TxAc), did not inhibit the LPS-induced IL-6 production at lower concentration (p?>?0.05). Surflex-Dock molecular modeling study was performed to simulate the binding capacity of compounds into the active site of the TNF-α (2AZ5), tumor protein P53 (2VUK), and NF-kappa-B (1RAM). The differential inhibition of cytokines by Tx and TxAc was further confirmed by high docking scores showing the high affinity to target proteins. Findings of the study demonstrated the comparatively greater role of Pluchea triterpene than its in situ produced acetate derivate in neuroinflammation-associated disorders.  相似文献   
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Extramedullary hematopoiesis (EMH) represents tumor-like proliferation of hemopoietic tissue which complicates chronic hemoglobinopathy. Intracranial EMH is an extremely rare occurrence. Magnetic resonance imaging (MRI) offers a precise diagnosis. It is essential to distinguish EMH from other extradural central nervous system tumors, because treatment and prognosis are totally different. Herein, we report the imaging findings of beta-thalassemia in a 13-year-old boy complaining of weakness of left side of the body and gait disturbance; CT and MRI revealed an extradural mass in the right temporoparietal region.  相似文献   
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An efficacious vaccine is needed to control Chlamydia trachomatis infection. In the murine model of Chlamydia muridarum genital infection, multifunctional mucosal CD4 T cells are the foundation for protective immunity, with antibody playing a secondary role. We previously identified four Chlamydia outer membrane proteins (PmpE, PmpF, PmpG and PmpH) as CD4 T cell vaccine candidates using a dendritic cell-based immunoproteomic approach. We also demonstrated that these four polymorphic membrane proteins (Pmps) individually conferred protection as measured by accelerated clearance of Chlamydia infection in the C57BL/6 murine genital tract model. The major outer membrane protein, MOMP is also a well-studied protective vaccine antigen in this system. In the current study, we tested immunogenicity and protection of a multisubunit recombinant protein vaccine consisting of the four Pmps (PmpEFGH) with or without the major outer membrane protein (MOMP) formulated with a Th1 polarizing adjuvant in C57BL/6, Balb/c and C3H mice. We found that C57BL/6 mice vaccinated with PmpEFGH + MOMP elicited more robust cellular immune responses than mice immunized with individual protein antigens. Pmps elicited more variable cellular immune responses than MOMP among the three strains of mice. The combination vaccine accelerated clearance in the three strains of mice although at different rates. We conclude that the recombinant outer membrane protein combination constitutes a promising first generation Chlamydia vaccine construct that should provide broad immunogenicity in an outbred population.  相似文献   
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The abysmal success rate of anticancer drugs in clinical trials, is in part, attributable to discordance between cultured cancer cells and patient tumors. While tumors in vivo, display a lower mitotic index, patient tumors portray much higher centrosomal aberrations, relative to in vitro cultured cells. The microenvironment too differs considerably between the in vitro and in vivo scenarios. Notably, another hallmark of cancer, hypoxia, is not recapitulated in cell lines cultured under normoxic conditions. These observations raise the possibility that hypoxia may be the missing link that explains the discordance between cell biological phenomena in vitro versus physiological conditions. Further, the interplay between hypoxia and centrosome amplification (CA) is relatively understudied. Recent research from our laboratory, geared toward examining the biological link between the two, has uncovered that hypoxia induces the expression of proteins (Plk4, Aurora A, Cyclin D) implicated in CA, in a hypoxia-inducible factor 1α (HIF-1α)-dependent context. Our studies evidence that hypoxia fuels CA that underlie intratumoral heterogeneity and metastatic potential of cancer cells. Given the advent of HIF-1α inhibitors, this research has ramifications in aiding patient risk stratification and designing new cancer drug therapies to facilitate clinical decision-making.  相似文献   
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