Techniques to resect the distal ureter in robotic/laparoscopic nephroureterectomy

Treatment of clinically-organ confined high grade urothelial carcinoma of the upper tract has historically comprised open nephroureterectomy,with the distal ureter and bladder cuff mobilized through a separate open pelvic incision.To decrease morbidity,urologists have increasingly adopted laparoscopy and robotics in performing nephroureterectomy.In many published series of laparoscopic nephroureterectomy,the distal ureter and bladder cuff are detached from the bladder endoscopically by a variation of the“pluck”technique,with the resulting bladder defect left to heal by prolonged indwelling urethral catheter drainage.While the distal ureter and bladder cuff can be excised laparoscopically,it does require advanced laparoscopic skills.With the wrist articulation and stereoscopic vision in robotic surgery,robotic nephroureterectomy(RNU)and bladder cuff excision can be performed in antegrade fashion to mimic the open technique together with the ability to intracorporeally close the bladder defect in a watertight,mucosa to mucosa fashion after excising the bladder cuff.In this review,we discuss the published minimally invasive techniques in resecting the distal ureter and bladder cuff during laparoscopic and RNU.

Investigation of confocal microscopy for differentiation of renal cell carcinoma versus benign tissue.Can an optical biopsy be performed?

Objective:Novel optical imaging modalities are under development with the goal of obtaining an“optical biopsy”to efficiently provide pathologic details.One such modality is confocal microscopy which allows in situ visualization of cells within a layer of tissue and imaging of cellular-level structures.The goal of this study is to validate the ability of confocal microscopy to quickly and accurately differentiate between normal renal tissue and cancer.Methods:Specimens were obtained from patients who underwent robotic partial nephrectomy for renal mass.Samples of suspected normal and tumor tissue were extracted from the excised portion of the kidney and stained with acridine orange.The stained samples were imaged on a Nikon E600 C1 Confocal Microscope.The samples were then submitted for hematoxylin and eosin processing and read by an expert pathologist to provide a gold-standard diagnosis that can later be compared to the confocal images.Results:This study included 11 patients,17 tissue samples,and 118 confocal images.Of the 17 tissue samples,10 had a gold-standard diagnosis of cancer and seven were benign.Of 118 confocal images,66 had a gold-standard diagnosis of cancer and 52 were benign.Six confocal images were used as a training set to train eight observers.The observers were asked to rate the test images on a six point scale and the results were analyzed using a web based receiver operating characteristic curve calculator.The average accuracy,sensitivity,specificity,and area under the empirical receiver operating characteristic curve for this study were 91%,98%,81%,and 0.94 respectively.Conclusion:This preliminary study suggest that confocal microscopy can be used to distinguish cancer from normal tissue with high sensitivity and specificity.The observers in this study were trained quickly and on only six images.We expect even higher performance as observers become more familiar with the confocal images.

入侵植物粗毛牛膝菊根际土壤和根系真菌群落会沿海拔扩散路径发生变化

与入侵植物相关的真菌群落可能会随着海拔发生变化,这可能会影响入侵植物的表现和入侵力。我们最近的研究表明,入侵植物粗毛牛膝菊(Galinsoga quadriradiata)的根系AMF侵染率随着海拔的升高而下降。然而,尚不清楚这是否与真菌群落沿海拔的变化相关。为此,我们采用高通量测序技术、功能分组和线性分析等方法,研究了秦巴山区的粗毛牛膝菊根际土壤和根系真菌群落组成与结构沿海拔的变化趋势。研究结果表明,粗毛牛膝菊根际土壤和根系真菌群落物种多样性和种类组成随海拔升高发生了显著变化。在根际土壤中真菌群落香农-威纳多样性指数随着海拔升高呈上升趋势,而在根系中则呈下降趋势。同时,在根际土壤中共生真菌的相对丰度随海拔高度没有发生显著变化,而在根系中呈下降趋势;在根际土壤中病原真菌的相对丰度随着海拔呈下降趋势,而在根系中呈上升趋势。这些研究结果暗示,该种在向研究区域高海拔地区入侵时,土壤共生真菌的供给并不会缺乏,但其与这些真菌之间建立并维持共生关系的能力降低了;在向高海拔扩张过程中,该种倾向于在根系中积累更多的病原真菌,而减少对共生真菌的依赖。这些研究结果说明,入侵植物与真菌群落之间的相互作用会沿着海拔梯度发生显著变化,植物地下部分与真菌的相互作用可能是我们理解外来种如何在高海拔环境中入侵成功的关键。