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Reza Zare,1 Magnus Grabe,2 Gregers G Hermann,3 Per-Uno Malmström4 1Department of Urology, Vestre Viken HF Bærum Hospital, Oslo, Norway; 2Department of Urology, Skåne University Hospital, University of Lund, Malmö, Sweden; 3Department of Urology, Herlev and Gentofte Hospital, Copenhagen University, Denmark; 4Department of Urology, Institute of Surgical Sciences, Uppsala University, Uppsala, Sweden Background: The aim of this prospective cohort study was to determine the feasibility of incorporating blue light flexible cystoscopy (BLFC) and biopsy/fulguration into routine outpatient follow-up of non-muscle invasive bladder cancer patients. Methods: The study included patients with non-muscle-invasive bladder cancer (NMIBC) who were scheduled for routine follow-up. Hexaminolevulinate was instilled in the outpatient department, and the bladder was examined under white light and then with BLFC. Biopsies were taken from all suspicious lesions. Small tumors and suspicious lesions were fulgurated on site; patients with larger lesions were referred to the operating room for resection. Results: The study included 69 patients, with a mean age of 70 years (range 33–89 years) and a mean duration since NMIBC diagnosis of 8 years. Most patients had high-grade cancer at initial diagnosis (52/69) and were at high risk of recurrence (48/69). Two patients per hour could be assessed using outpatient BLFC. Preparation and instillation of hexaminolevulinate took less than 10 minutes per patient, and patients had an additional waiting time of 45–60 minutes following instillation, while the hexaminolevulinate solution was retained in the bladder before examination. Eleven patients had histologically confirmed tumors that were identified using both white light flexible cystoscopy and BLFC. An additional three patients had tumors that were identified by BLFC only: two with Ta tumors and one with carcinoma in situ. Of the 14 patients with confirmed tumors, 11 could be managed on site with fulguration, whereas three were referred to the operating room. No adverse events attributable to BLFC were reported. Conclusion: Routine outpatient management of patients with NMIBC using BLFC and on-site biopsy/fulguration is feasible, despite the additional time required for hexaminolevulinate instillation, and appears to allow early detection of recurrent lesions, which can be fulgurated without the need for hospitalization. Keywords: bladder cancer, blue light, diagnosis, flexible cystoscopy, hexaminolevulinate, outpatients

Intracellular organelles have characteristic pH ranges that are set and maintained by a balance between ion pumps, leaks, and internal ionic equilibria. Previously, a thermodynamic study by Rybak et al. (Rybak, S., F. Lanni, and R. Murphy. 1997. Biophys. J. 73:674-687) identified the key elements involved in pH regulation; however, recent experiments show that cellular compartments are not in thermodynamic equilibrium. We present here a nonequilibrium model of lumenal acidification based on the interplay of ion pumps and channels, the physical properties of the lumenal matrix, and the organelle geometry. The model successfully predicts experimentally measured steady-state and transient pH values and membrane potentials. We conclude that morphological differences among organelles are insufficient to explain the wide range of pHs present in the cell. Using sensitivity analysis, we quantified the influence of pH regulatory elements on the dynamics of acidification. We found that V-ATPase proton pump and proton leak densities are the two parameters that most strongly influence resting pH. Additionally, we modeled the pH response of the Golgi complex to varying external solutions, and our findings suggest that the membrane is permeable to more than one dominant counter ion. From this data, we determined a Golgi complex proton permeability of 8.1 x 10(-6) cm/s. Furthermore, we analyzed the early-to-late transition in the endosomal pathway where Na,K-ATPases have been shown to limit acidification by an entire pH unit. Our model supports the role of the Na,K-ATPase in regulating endosomal pH by affecting the membrane potential. However, experimental data can only be reproduced by (1) positing the existence of a hypothetical voltage-gated chloride channel or (2) that newly formed vesicles have especially high potassium concentrations and small chloride conductance.

One of the most common uses of a course management system in the on-campus environment is to offer lecture resources to students. Few researchers have investigated how students use such resources. This study considers student use of lecture resources that offer a representation of the lecture presented (i.e. lecture outline, lecture summary, audio recording) and the relationship of the use of such resources to examination performance and attendance. The present research is argued to be an extension of research that investigated the benefits of providing students instructor notes conducted some 30 years ago. The Internet provides a practical way to apply some of these ideas and to collect data on the reaction of students to the opportunity to view lecture resources. Students made very little use of the audio recordings. We suggest audio recordings may be regarded by students as less efficient and less useful than text-based lecture summaries. The use of online lecture resources, lecture attendance, and examination performance were positively related. For one of three examinations, there was a significant negative interaction of note use and attendance in predicting examination performance providing some support for the hypothesis that students may be able to successfully compensate by viewing online lecture resources when unable to attend class. Because students in this study were not asked to explain their use of these resources, the present findings are regarded as speculative. However, given the interests of many practitioners in providing students lecture resources, the descriptive data and the relationships observed here encourage additional investigation.

Accurate identification of what a learner does not know is essential for efficient self-directed learning. The accuracy of this awareness, often described as calibration, has been operationalized in several ways. Calibration data are often collected in applied settings by having students predict a future examination score. This method is efficient but not a direct measurement of the awareness of specific strengths and weaknesses. Online technology allows a practical way to collect more specific, local data; that is, the accuracy of confidence ratings for individual assessment items. These two methods of estimating calibration, global and local, were contrasted as predictors of performance in an introductory college course. Both measures were demonstrated to be significant and unique predictors of future examination performance. Online study environments requiring certitude judgments for study questions and offering immediate opportunities for review may offer the means for improving the efficiency of self-directed learning. [ABSTRACT FROM AUTHOR]