Evidence that recipient CD8+ T cell depletion does not alter development of chronic vascular rejection in a rat heart allograft model

Progressive chronic vascular rejection is a central feature of indefinitely surviving WF.1L LEW/Gut (RT1(1)) heart grafts transplanted to LEW (RT1(1)) recipients in unmodified donor-recipient combinations. At 70 days posttransplantation, large vessels of the grafts are characterized by the presence of vasculitis, vasculitis with associated variable myointimal thickening, and occlusive myointimal thickening with minimal or absent concomitant vasculitis. To assess the potential role of CD8+ T cells as critical effectors of chronic vascular rejection in this model, LEW recipients of WF.1L heart grafts were effectively depleted of CD8+ T cells as a result of prior thymectomy and anti-CD8 (MRC OX8) monoclonal antibody administration prior to transplantation. WF.1L heart grafts transplanted to LEW recipients that had undergone prior sham thymectomy and MRC OX8 administration, or thymectomy and administration of antibody-free culture supernatant, provided appropriate controls. At 70 days posttransplantation, large vessels of WF.1L heart grafts in all 3 transplantation groups showed similar morphologic features, which were comparable to those observed in heart grafts of long-surviving unmodified donor-recipient pairs. This study has shown that profound selective depression of recipient CD8+ T cells does not alter the characteristic features of chronic vascular rejection in this rat cardiac model, and provides evidence that CD8+ T cells play no critical role in the initiation or development of progressive vascular damage in this setting.     

On the slowly rising phase of the sodium gating current in the squid giant axon

High-resolution records of the sodium gating current in the squid giant axon demonstrate the existence of a slowly rising phase that is first apparent at pulse potentials slightly below zero, and becomes increasingly pronounced at more positive potentials. At +80 mV the current reaches its peak with a delay of 30 microseconds at 10 degrees C. It is suggested that this current is generated by the first two steps labelled R-->P and P-->A in the S4 units of all four domains of the series-parallel gating system, activating the channel before its opening by the third steps A-->B in domains I, II and III in conjunction with hydration. The kinetics of the slowly rising phase can only be explained by the incorporation of an appropriate degree of voltage-dependent cooperativity between the S4 voltage-sensors for their two initial transitions.     

制造窗光与黑白电影风格人像

正这里,我们会告诉大家,如何使用简单的影调调整技巧将高调影像与黑色电影风格糅合在一起。简单的Photosh0p调整就能够让一幅照片变得大不一样。我们只需要在影调上略做手脚,就能让一幅照片所表现的氛围发生彻底的转变。正如我们在教程中所做的那样,一幅寻常的肖像作品调整前后大相径庭。首先,我们的目标是在不损伤皮肤细节的前提下创     

高阶技巧合集降噪锐化两不误

正在我们的帮助下,掌握Photoshop和Adobe Camera RaW中的各类锐化与降噪技巧。几乎任何一张照片的处理都离不开降噪与锐化两大操作,这一点想必大家都有所体会。尤其是本文所使用的范例图片,额外的锐化能给鸟类华丽的羽毛带来锦上添花的效果。如何将高明的锐化技巧运用于自己的修片流程,是本文的重点。在这个过程中,大家将会接触到Photoshop CC中得到大幅改善的锐化和图片放大功能。教程所介绍的不同技巧是为了帮助大家掌握它们的使用方式,更重要的是理解它们的应用场合,而不是依葫芦画瓢在每幅照     

Lightroom修正色温与眩光

正我们来带领大家体验Lightroom中足以媲美Photoshop的图像调整能力,尤其是在调节色温与抑制画面眩光等方面。随着Photoshop的付费模式由过去的一次性付费变成按月付费,之前因为价格高不可攀而却步的人纷纷有些行动。但无论如何,这依旧不是一笔小钱。作为摄影师,我们是否真的需要Photosh0p,更便宜的Lightroom是     

Left ventricular diastolic function in hypertensive patients with unstable angina and single coronary artery disease

The present study was performed to investigate left ventricular diastolic (LVD) function in hypertensive patients with unstable angina. Three groups of 17 patients each were studied. Group 1 consisted of hypertensives with unstable angina (HTU); group 2, normotensives with unstable angina (NTU); and group 3, untreated, uncomplicated hypertensives (HT). The LVD function was assessed echocardiographically by transmitral valve Doppler flow to measure the ratio between the early diastolic filling (E) and the atrial contraction phase (A). An E/A ratio of < 1 was suggestive of LVD dysfunction. Left ventricular mass (LVM), from an M-mode echocardiogram using the Penn-Cube formula, was corrected to body surface area (LVM/S) using a standard nomogram. Data are represented as median values and analyzed by Mann-Whitney test. P was significant at < .05. The HTU group had an E/A ratio of 0.8, and the NTU and HT groups had ratios of 1.17 and 1.1, respectively. There was significant diastolic dysfunction in the HTU group compared with the NTU and HT groups (P = .037 and .049, respectively). Although the LVM/S was significantly higher in the HTU group when compared with the HT group (110.6 and 96.9, respectively, P = .017), there was no significant difference between the HTU and NTU groups (123.1), P = .67. Hypertensive patients with unstable angina have significant LVD dysfunction that seems to be independent of LVM and ischemia. This may be attributable to increased stiffness of the left ventricle or structural left ventricular abnormalities.     

Pulmonary transplantation

OBJECTIVE: More than 2700 lung transplants have been performed since the initial clinical success in 1983. The evolution in the techniques of lung transplantation and patient management and the effects on results are reviewed. SUMMARY BACKGROUND DATA: Improvements in donor management, lung preservation, operative techniques, immunosuppression management, infection prophylaxis and treatment, rejection surveillance, and long-term follow-up have occurred in the decade following the first clinically successful lung transplant. A wider spectrum of diseases and patients treated with lung transplant have accentuated the shortage of suitable lung donors. The organ shortage has led to the use of marginal donors and a limited experience using living, related donors. METHODS: Changes in techniques and patient selection and management are reviewed and controversial issues and problems are highlighted. RESULTS: One-year survival of greater than 90% for single-lung transplant recipients and greater than 85% for bilateral lung transplant recipients have been achieved. Complications caused by airway complications has been reduced greatly. Obliterative bronchiolitis develops in 20% to 50% of long-term survivors and is the leading cause of morbidity and mortality after the first year after transplant. CONCLUSIONS: Lung transplantation has evolved into an effective therapy for a wide variety of causes of end-stage lung disease. Wider applicability requires solutions to the problems of donor shortage and development of obliterative bronchiolitis.