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Previously, we reported that sanguinarine, a phytoalexin with antimicrobial, anti‐oxidant, anti‐inflammatory and pro‐apoptotic effects, is a risk factor for normal embryonic development that triggers apoptotic processes in the inner cell mass of mouse blastocysts, causing decreased embryonic development and cell viability. In the current study, we investigated the deleterious effects of sanguinarine on mouse oocyte maturation, in vitro fertilization (IVF), and subsequent pre‐ and postimplantation development both in vitro and in vivo. Notably, sanguinarine significantly impaired mouse oocyte maturation, decreased IVF rates, and inhibited subsequent embryonic development in vitro. Preincubation of oocytes with sanguinarine during in vitro maturation induced an increase in postimplantation embryo resorption and a decrease in mouse fetal weight. In an in vivo animal model, 1 to 5 μM sanguinarine, provided in drinking water, caused a decrease in oocyte maturation and IVF, and led to deleterious effects on early embryonic development. Importantly, preincubation of oocytes with a caspase‐3‐specific inhibitor effectively blocked sanguinarine‐triggered deleterious effects, clearly implying that embryonic injury induced by sanguinarine is mediated by a caspase‐dependent apoptotic mechanism. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 946–955, 2015.  相似文献   
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Live guinea pig cytomegalovirus (CMV) vaccine was prepared after 11 serial passages in tissue culture; noninfectious envelope antigen vaccine was prepared by n-octyl glucoside treatment of CMV-derived dense bodies and virions. Hartley strain guinea pigs immunized with either vaccine were compared with guinea pigs inoculated with virulent, salivary gland-passaged CMV (approximating natural infection), with passively immunized animals, and with nonimmune controls. All vaccinated animals had neutralizing antibodies to CMV. After challenge with virulent CMV, animals previously inoculated with either tissue culture-passaged or virulent CMV were protected against acute viremia and death; pregnant animals previously inoculated with live CMV vaccine had lower incidences of viremia and generalized maternal and fetal infection. Envelope antigen-vaccinated and passively immunized pregnant animals showed acute viremia after similar challenge with virulent virus; however, infection was less generalized than that in control animals, and CMV was not isolated from the fetuses of these vaccinated mothers.  相似文献   
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To assess the diagnostic value of transesophageal two-dimensional echocardiography (TEE) as compared with transthoracic echocardiography (TTE), TTE and TEE were performed in eight consecutive patients (age range from 20 to 76 years, six male and two female) with clinical evidence of malignant tumors arising from the liver (n = 1), lung (n = 3), larynx (n = 1), osteogenic sarcoma (n = 1), lymphoma (n = 1), and yolk sac tumor in the anterior mediastinum (n = 1). In one case, the gastroscope could not be inserted because of tumor compression of the esophagus. Transesophageal echocardiography provided superior imaging in the detection of intracavitary metastatic lesions. In the case of right ventricular outflow tract tumor and greater vessel involvement, TTE may provide more imaging than TEE due to a blind area in this region by the transesophageal approach. In conclusion, TEE is complementary to TTE in the diagnosis of metastatic cardiac tumor.  相似文献   
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This review provides a summary statement of recommended implementations of arterial spin labeling (ASL) for clinical applications. It is a consensus of the ISMRM Perfusion Study Group and the European ASL in Dementia consortium, both of whom met to reach this consensus in October 2012 in Amsterdam. Although ASL continues to undergo rapid technical development, we believe that current ASL methods are robust and ready to provide useful clinical information, and that a consensus statement on recommended implementations will help the clinical community to adopt a standardized approach. In this review, we describe the major considerations and trade‐offs in implementing an ASL protocol and provide specific recommendations for a standard approach. Our conclusion is that as an optimal default implementation, we recommend pseudo‐continuous labeling, background suppression, a segmented three‐dimensional readout without vascular crushing gradients, and calculation and presentation of both label/control difference images and cerebral blood flow in absolute units using a simplified model. Magn Reson Med 73:102–116, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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TRK‐100STP, a sustained‐release preparation of the orally active prostacyclin analogue beraprost sodium, targets renal hypoxia. This study aimed to show the superiority of TRK‐100STP over placebos in patients with chronic kidney disease (with either primary glomerular disease or nephrosclerosis) to determine the recommended dose. CASSIOPEIR (Chronic Renal Failure Asian Study with Oral PGI2 Derivative for Evaluating Improvement of Renal Function) was a randomized, double‐blind, placebo‐controlled study conducted at 160 sites in seven Asia‐Pacific countries and regions. Eligible patients (n = 892) were randomized to TRK‐100STP 120, 240 μg, or placebo for a treatment period of up to 4 years. The primary efficacy endpoint was time to first occurrence of a renal composite: doubling of serum creatinine or occurrence of end‐stage renal disease. No significant differences were observed in composite endpoints between TRK‐100STP and placebo (P = 0.5674). Hazard ratios (95% CI) in the TRK‐100STP 120 and 240 μg vs. placebo groups were 0.98 (0.78, 1.22) and 0.91 (0.72, 1.14), respectively. The overall incidence of adverse events and adverse drug reactions was comparable between treatment arms.  相似文献   
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The activation of eukaryotic SLO K+ channels by intracellular cues, mediated by a cytoplasmic structure called the gating ring, is central to their physiological roles. SLO3 channels are exclusively expressed in mammalian sperm, where variations of intracellular pH are critical to cellular function. Previous studies primarily focused on the mouse SLO3 orthologue and revealed that, in murine sperm, SLO3 mediates a voltage- and alkalization-activated K+ current essential to male fertility. Here we investigate the activation of the human SLO3 channel by intracellular pH at the functional and structural level. By using electrophysiology in a heterologous system, we show that human SLO3 opens upon intracellular pH increase and that its expression and functional properties are modulated by LRRC52, a testis-specific accessory subunit. We next present the crystal structure of the human SLO3 gating ring. Comparison with the known structures of the corresponding domain from SLO1, a Ca2+-activated homologue, suggests that the SLO3 gating ring structure may represent an open state. Together, these results present insights into the function of a protein expected to be critical for human reproduction and provide a framework to study the mechanism of pH gating in SLO3 channels.  相似文献   
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We compared findings from intraoperative live/real time three-dimensional transesophageal echocardiography (3DTEE) and two-dimensional transesophageal echocardiography (2DTEE) with surgery in 67 patients having aortic aneurysm and/or aortic dissection. Of these, 20 patients had aortic aneurysm without dissection, 21 aortic aneurysm and dissection, and 26 aortic dissection without aneurysm. 3DTEE diagnosed the type and location of aneurysm correctly in all patients unlike 2DTEE, which missed an aneurysm in one case. There were four cases of aortic aneurysm rupture. Three of them were diagnosed by 3DTEE but only one by 2DTEE, and one missed by both techniques. The mouth of saccular aneurysm, site of aortic aneurysm rupture, and communication sites between perfusing and nonperfusing lumens of aortic dissection could be viewed en face only with 3DTEE, enabling comprehensive measurements of their area and dimensions as well as increasing the confidence level of their diagnosis. In all patients with aortic dissection, 3DTEE enabled a more confident diagnosis of dissection because the dissection flap when viewed en face presented as a sheet of tissue rather than a linear echo seen on 2DTEE which can be confused with an artifact. 2DTEE missed dissection in one patient. In six cases the dissection flap involved the right coronary artery orifice by 3DTEE and surgery. These were missed by 2DTEE. Aortic regurgitation severity was more comprehensively assessed by 3DTEE than 2DTEE. Aneurysm size by 3DTEE correlated well with 2DTEE and surgery/computed tomography scan. In conclusion, 3DTEE provides incremental information over 2DTEE in patients with aortic aneurysm and dissection.  相似文献   
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