Aortic root motion remodeling after aortic valve replacement--implications for late aortic dissection

Aortic root motion was previously identified as an additional risk factor for aortic dissection. This study analyzed if the magnitude of aortic root motion changed in patients after aortic valve replacement (AVR) and acute proximal aortic dissection. An institutional database (1984-2005) was used to measure the downward motion of the aortic root (perpendicular to the plane of the sinotubular junction) in contrast injections in 48 patients with aortic insufficiency (AI), aortic stenosis (AS) and proximal aortic dissection pre- and postoperatively, when available. Postoperative aortic root motion was significantly reduced after AVR for AI, while it was significantly increased after AVR for AS. By contrast, aortic root motion was unchanged when functional AI due to paravalvular leak was present post-AVR for AI. In patients with acute aortic dissection, both aortic root motion and aortic diameter were unchanged from pre-dissection. However, in patients who dissected again, aortic root motion was significantly smaller than pre-dissection, and the aortic diameter was significantly less than at first dissection. Removal of aortic stenosis was associated with increased aortic root motion, theoretically heightening the threat of dissection posed to the aortic wall by mechanical stress, although this was not confirmed by our study of dissection patients. Yet, mechanical principles command to include higher magnitude of aortic root motion during follow-up of patients after AVR as an additional risk factor for dissection.     

参三七皂甙Rg1对实验性血栓形成的影响及其机制探讨

用大鼠动静脉血栓形成模型,研究参三七皂甙Rg₁抗血栓作用。结果表明,参三七皂甙Rg₁可明显降低实验性血栓形成,对大鼠血浆纤溶系统亦有明显作用,可升高血浆中组织纤溶酶原激活物(t-PA)活性和活性型t-PA百分比,降低组织纤溶酶原激活物抑制剂(PAI)活性。同时利用培养大鼠血管内皮细胞实验,发现Rg₁可以剂量依赖性提高血管内皮细胞一氧化氮(NO)释放。提示Rg₁抗血栓作用与增强纤溶系统活性,促进血管内皮NO释放有关。     

间硝地平对左室肥厚大鼠左室舒张功能及心脑线粒体和血管组织钙含量的影响

用肾性高血压左室肥厚(LVH)大鼠模型,观察了间硝地平(m-Nif)和硝苯地平(Nif)长期给药(ig20mg·kg^-1·d^-1持续9周)对左室舒张功能、左心室肌和大脑线粒体及血管钙含量的影响。与假手术组相比,LVH组左室顺应性明显下降,僵硬度增高,左心室肌和大脑线粒体及尾动脉和主动脉钙含量增加。与LVH组相比,m-Nif和Nif各组左室顺应性改善,僵硬度降低(P<0.01),左心室肌线粒体及尾动脉和主动脉钙含量较LVH组显著降低(P<0.01)。两药在作用强度上无显著差异。     

Innovation in clinical method: diabetes care and negotiating skills

The development of a method to facilitate clinical negotiationwith diabetic patients is described. The principles of the methodincorporate patient centredness, an assessment of readinessto change and some elements of motivational interviewing. Asimple low cost technology is part of the innovative method.Details of the method and its application are published beforethe results of a randomized controlled trial to ensure thatthe techniques are in the public domain before the outcome ofthe trial is known.     

Leucocytoclastic vasculitis associated with hepatitis C virus antibodies

The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but recently hepatitis C virus (HCV) has been suggested as trigger of autoimmunity. We report a case of a 26-yr-old patient with purpura due to leucocytoclastic vasculitis associated with hepatitis C virus infection. Laboratory findings showed AST, ALT, gamma GT within normal limits, positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti- cardiolipin antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic antibodies with perinuclear pattern were also present. A skin biopsy specimen of a purpuric lesion showed leucocytoclastic vasculitis with small vessel thrombosis and perivascular deposition of IgM and fibrinogen on immunofluorescence study. This case shows a role of HCV in leucocytoclastic vasculitis; it is possible that this HCV can induce autoimmunity independently of cryoglobulins and liver involvement.      

Central thrombi in pulmonary arterial hypertension detected by MR imaging

Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.     

Primary classic Kaposi''s sarcoma of the penis: report of a case and review

Kaposi's sarcoma is a vascular tumour of multifocal origin occurring primarily on the extremities. The case of a 45-year-old HIV negative and HHV-8 positive man with an asymptomatic reddish macular lesion on the inner layer of the prepuce is described. Although primary penile Kaposi's sarcoma is a relatively uncommon disorder in HIV negative men, dermatologists and venereologists should consider this possibility when treating non-specific penile lesions. A minimal penile lesion with non-distinctive clinical features may sometimes be the exclusive manifestation of Kaposi's sarcoma, making histologic evaluation necessary to establish the diagnosis.     

UROKIN: A Software to Enhance Our Understanding of Urogenital Motion

Transperineal ultrasound (TPUS) allows for objective quantification of mid-sagittal urogenital mechanics, yet current practice omits dynamic motion information in favor of analyzing only a rest and a peak motion frame. This work details the development of UROKIN, a semi-automated software which calculates kinematic curves of urogenital landmark motion. A proof of concept analysis, performed using UROKIN on TPUS video recorded from 20 women with and 10 women without stress urinary incontinence (SUI) performing maximum voluntary contraction of the pelvic floor muscles. The anorectal angle and bladder neck were tracked while the motion of the pubic symphysis was used to compensate for the error incurred by TPUS probe motion during imaging. Kinematic curves of landmark motion were generated for each video and curves were smoothed, time normalized, and averaged within groups. Kinematic data yielded by the UROKIN software showed statistically significant differences between women with and without SUI in terms of magnitude and timing characteristics of the kinematic curves depicting landmark motion. Results provide insight into the ways in which UROKIN may be useful to study differences in pelvic floor muscle contraction mechanics between women with and without SUI and other pelvic floor disorders. The UROKIN software improves on methods described in the literature and provides unique capacity to further our understanding of urogenital biomechanics.     

Chagas' disease diagnosis: evaluation of several tests in blood bank screening

Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease.