To date, the clinical use of functional near-infrared spectroscopy (NIRS) to detect cerebral ischemia has been largely limited to surgical settings, where motion artifacts are minimal. In this study, we present novel techniques to address the challenges of using NIRS to monitor ambulatory patients with kidney disease during approximately eight hours of hemodialysis (HD) treatment. People with end-stage kidney disease who require HD are at higher risk for cognitive impairment and dementia than age-matched controls. Recent studies have suggested that HDrelated declines in cerebral blood flow might explain some of the adverse outcomes of HD treatment. However, there are currently no established paradigms for monitoring cerebral perfusion in real-time during HD treatment. In this study, we used NIRS to assess cerebral hemodynamic responses among 95 prevalent HD patients during two consecutive HD treatments. We observed substantial signal attenuation in our predominantly Black patient cohort that required probe modifications. We also observed consistent motion artifacts that we addressed by developing a novel NIRS methodology, called the HD cerebral oxygen demand algorithm (HDCODA), to identify episodes when cerebral oxygen demand might be outpacing supply during HD treatment. We then examined the association between a summary measure of time spent in cerebral deoxygenation, derived using the HD-CODA, and hemodynamic and treatment-related variables. We found that this summary measure was associated with intradialytic mean arterial pressure, heart rate, and volume removal. Future studies should use the HD-CODA to implement studies of real-time NIRS monitoring for incident dialysis patients, over longer time frames, and in other dialysis modalities.

Objective of the study: We used fluorescence imaging methods of apoptosis and necrosis in human renal carcinoma A498 tumor cells in vitro to reveal the indicated forms of cell death under the combined effect of flavonoid-containing extract of Gratiola officinalis and cytostatic (cyclophosphamide). Materials and methods: The dyes were propidium iodide and acridine orange, which were used in the "alive and dead" test. This test helped us to identify the total number of dead cells in the forms of necrosis and apoptosis and the number of cells in which apoptosis had started, it was characterized by the appearance of apoptotic bodies or nucleus pyknosis. Results: We found the most pronounced cytotoxic activity at the ratio of extract of Gratiola officinalis and cyclophosphamide concentrations of 1:1. The number of living cells decreased when exposed to the ratio of extract and cytostatic concentrations of 2:1. When the ratio of concentration of the extract relative to the cytostatic increased to 3:1, the cytostatic activity of the extract began to appear, the total number of tumor cells decreased. The number of cells with nucleus pyknosis and the number of cells with apoptosis signs significantly increased at a 3:1 ratio of extract and cytostatic concentrations, which confirms the presence of pro-apoptotic activity of the studied combination. This trend indicates the dependence of a certain form of cell death (apoptosis, necrosis) on the ratio of extract and cytostatic doses, and it also demonstrates the cytostatic and cytotoxic effects of this combination. Conclusion: Fluorescence methods of investigation in the "alive and dead" test allowed us to visualize the forms of cell death of human kidney carcinoma A498 by combined exposure to the flavonoid-containing extract of Gratiola officinalis and cytostatic (cyclophosphamide) 24 h after exposure. We found that the combination with a concentration ratio of the extract and cyclophosphamide of 3:1 has the greatest effectiveness due to stimulation of the cytostatic effect and cytotoxic effect.

光学相干层析成像(OCT)具有分辨率高、成像深度深和成像速度快的优点,为评估肾脏状态提供了一种新方法。肾脏缺血再灌注会导致肾功能单元发生损伤,采用无损成像可以实时快速地评价肾脏的活性状态。采用中心波长为1300 nm的SDOCT(spectral-domain OCT)对Wistar大鼠肾脏进行活体二维和三维成像,图像能够清晰地显示肾皮质层的肾小管微结构。结果表明:OCT对肾脏缺血再灌注过程响应灵敏,在肾脏状态评估方面具有广阔的应用前景。

Adriamycin (doxorubicin), a common cancer chemotherapeutic drug, can be used to induce a model of chronic progressive glomerular disease in rodents. In our studies, we evaluated renal changes in a rat model after Adriamycin injection using two-photon microscopy (TPM), optical coherence tomography (OCT) and Doppler OCT (DOCT). Taking advantage of deep penetration and fast scanning speed for three-dimensional (3D) label-free imaging, OCT/DOCT system was able to reveal glomerular and tubular pathology noninvasively and in real time. By imaging renal pathology following the infusion of fluorophore-labeled dextrans of different molecular weights, TPM can provide direct views of glomerular and tubular flow dynamics with the onset and progression of renal disease. Specifically, glomerular permeability and filtration, proximal and distal tubular flow dynamics can be revealed. 6–8 weeks after injection of Adriamycin, TPM and OCT/DOCT imaging revealed glomerular sclerosis, compromised flow across the glomerular wall, tubular atrophy, tubular dilation, and variable intra-tubular flow dynamics. Our results indicate that TPM and OCT/DOCT provide real-time imaging of renal pathology in vivo that has not been previously available using conventional microscopic procedures.

本研究旨在探索被动吸烟对小鼠肾草酸钙结石模型形成的影响。将55只小鼠随机分为正常对照组(A组) 、模型组1(B组)、模型组2(C组)、模型3组(D组)。A组正常对照组予以单纯生理盐水灌胃; B组诱石+被动吸烟组予以诱石剂灌胃(含0.75%乙二醇、0.75%氯化铵), 同时将小鼠放入吸烟染毒箱建立被动吸烟模型; C组单纯诱石灌胃组予以单纯诱石剂灌胃; D组单纯被动吸烟组予以等量生理盐水灌胃的同时将小鼠放入吸烟染毒箱建立被动吸烟模型。实验期间观察小鼠的进食进水情况、活动情况、生命体征及个体体毛等变化。分别于造模 7、14、21、28 d收集尿液进行尿草酸和尿钙含量的测定; 于造模结束后采集小鼠血清比较血肌酐浓度; 剖取肾脏称量并计算肾脏系数。造模3 d后, B、C两组小鼠出现爬行困难, 部分灌胃后出现深大呼吸, 活动减弱, 食欲减退, 体毛无光泽, B组小鼠较 C组小鼠表现更明显: 造模 7 d 后, B、C组开始出现不同数量的动物死亡, 且 B组死亡率明显高于 C组; 造模21天后, D组小鼠也开始出现死亡, 但A组小鼠实验中均未观察到死亡。不同时间点比较, B、C组小鼠尿草酸、尿钙、血肌酐浓度均高于 正常对照A组和单纯被动吸烟D组(P<0.05), 同时发现, B组(诱石灌胃+被动吸烟)尿草酸、尿钙浓度均明显高于 C组(诱石灌胃)(P<0.05)。与A组和D组比较, 模型组B、C组小鼠肾脏系数均明显增加, 差异具有统计学意义 (P<0.05)。结果表明, 被动吸烟可促进小鼠草酸钙型肾结石的形成。

目的:应用三维能量多普勒超声技术探讨成人常染色体显性多囊肾病(ADPKD)患者肾脏血流灌注的改变与血压的关系.方法:选取79例ADPKD患者;对照组86例,其中包括62例原发性高血压(EH)患者以及24例血压正常的健康成年人.使用三维能量多普勒超声采集肾脏三维能量图像并应用VOCAL分析软件得出相关参数指标:血管指数 (VI)、血流指数 (FI)、血管血流指数 (VFI)及肾脏总体积.结果:(1) 与同级别血压水平的对照组比较,在ADPKD患者血压正常时VI就开始减低、肾脏总体积就开始增大(P<0.05);(2)ADPKD合并高血压1级、2级、3级患者与同级别血压水平的对照组相比,其VI明显下降、肾脏总体积显著增大(P<0.01),预示着ADPKD疾病的进展,ADPKD血流动力学变化与血压的变化关系密切.结论:ADPD患者血流动力学的变化比血压的变化更敏感.故早期对多囊肾患者肾脏血流动力学进行监测,对于评估病情、判定疗效、指导临床治疗具有重要意义.

Au–Ft, as a green synthesized nanoparticle, is composed of a ferritin nanocage enclosing a pair of Au nanoclusters inside. Our previous study has demonstrated that Au–Ft can be an excellent fluorescent probe for whole body imaging of mice with kidney specific targeting. But, the accurate localization of Au–Ft in kidney is still absent. In the current study, we detected and assessed the cellular and subcellular localization of Au–Ft in renal cortex and medulla of nu/nu mice after tail vein injection by using Nuance optical system (CRi, Woburn, USA) and inForm intelligent image analysis software based on single cell segmentation. We obtained the fluorescence intensity and cellular location of kidney-targeting Au–Ft probe in particular cell of renal glomerulus or renal tubules, which provided valuable proofs to clarify the mechanism of Au–Ft selective enrichment in kidney and the associated metabolic processes.

Accepted 15 November 2013 Published 2 January 2014 While the laser speckle imaging (LSI) is a powerful tool for multiple biomedical applications, such as monitoring of the blood flow, in many cases it can provide additional information when combined with spatio-temporal rhythm analysis. We demonstrate the application of Graphics Processing Units (GPU)-based rhythm analysis for the post processing of LSI data, discuss the relevant structure of GPU-based computations, test the proposed technique on surrogate 3D data, and apply this approach to kidney blood flow autoregulation. Experiments with surrogate data demonstrate the ability of the method to extract information about oscillation patterns from noisy data, as well as to detect the moving source of the rhythm. The analysis of kidney data allow us to detect and to localize the dynamics arising from autoregulation processes at the level of individual nephrons (tubuloglomerular feedback (TGF) rhythm), as well as to distinguish between the TGF-active and the TGF-silent zones.

Acute tubular necrosis (ATN) induced by ischemia is the most common insult to donor kidneys destined for transplantation. ATN results from swelling and subsequent damage to cells lining the kidney tubules. In this study, we demonstrate the capability of optical coherence tomography (OCT) to image the renal microstructures of living human donor kidneys and potentially provide a measure to determine the extent of ATN. We also found that Doppler-based OCT (i.e., DOCT) reveals renal blood flow dynamics that is another major factor which could relate to posttransplant renal function. All OCT/DOCT observations were performed in a noninvasive, sterile and timely manner on intact human kidneys both prior to (ex vivo) and following (in vivo) their transplantation. Our results indicate that this imaging model provides transplant surgeons with an objective visualization of the transplant kidneys prior and immediately post transplantation.