Autofluorescence spectroscopy of oral leukoplakia using an artificial neural network

Objective. Early detection of oral cancer and premalignant lesions can improve the cure rate and reduce the morbidity of treatment. However, the incidence of oral cancer and precancer is low and risk groups are screened on a regular basis. Inspection is the most commonly used method of detection. Animal experiments have shown that premalignant lesions and squamous cell carcinoma of the oral mucosa can be detected by in‐vivo autofluorescence spectroscopy (AFS). Patients and methods. The experimental group consisted of 11 men and 10 women, mean age 60 years (range 30–81) In 22 oral leukoplakias AFS was performed, using a xenonlamp with a monochromator for illumination and an optical multichannel analyser for spectroscopy. The wavelength of the excitation light was 420 nm and AFS was recorded between 465 and 650 nm. Autofluorescence spectroscopy was measured in the centre and the border of the lesion, as well as in the healthy surrounding tissues and the contralateral counterpart. Data were analysed by using an artificial neural network. Results. The sensitivity of this system in the detection of oral leukoplakia was 86% with a specificity of 100%. With AFS homogeneous leukoplakia was recognized with a 73% sensitivity and 82% specificity. For non‐homogeneous lesions the sensitivity was 64% and the specificity 94%. In this material a correlation with histological classification has as yet not been found. Conclusion. This pilot study showed that oral leukoplakia can be detected with AFS. The artificial neural network was very valuable to analyse the data. Further research is justified to determine the value of AFS in the detection of oral cancer and premalignant lesions.     

Spontaneous luminal disequilibrium pH in S3 proximal tubules. Role in ammonia and bicarbonate transport.

We determined whether a spontaneous luminal disequilibrium pH, pHdq (pH measured - pH equilibrium), was present in isolated perfused rabbit S2 and S3 proximal tubules. Luminal pH was measured by perfusing with the fluorescent pH probe 1,4-DHPN, and the equilibrium pH was calculated from the measured collected total CO2 and dissolved CO2 concentrations. S2 tubules failed to generate a spontaneous pHdq. S3 tubules generated a spontaneous acidic pHdq of -0.46 +/- 0.15 (P less than 0.05), which was obliterated following the addition of carbonic anhydrase (0.1 mg/ml) to the perfusate. In S3 tubules perfused and bathed in 4 mM total ammonia, luminal total ammonia rose from 4.08 +/- 0.05 mM (perfusate) to 4.95 +/- 0.20 mM (collected fluid) (P less than 0.02). Carbonic anhydrase added to the perfusate prevented the rise in the collected total ammonia concentration. We conclude that the rabbit S3 proximal tubule lacks functional luminal carbonic anhydrase. The acidic pHdq in the S3 segment enhances the diffusion of NH3 into the lumen. In contrast, the S2 segment has functional luminal carbonic anhydrase.     

Participatory inquiry with a colleague: an innovative faculty development process

Clinical evaluation is central to the aims of nursing education; however, little has been written about the actual evaluative practices of nurse educators and the sources of influence on those practices. In this article, we describe our experience as co-investigators into the evaluation practices of one of us (J.A.J.) and overview some of the challenges and opportunities of participatory inquiry. We describe how J.A.J.'s involvement in this research project encouraged her to explore her evaluative practices in a meaningful way, which moved her to a place of deeper understanding about her work and transformed her as a nurse educator. As a result of this study, we are convinced of the necessity for a faculty development process whereby colleagues commit to a critical inquiry process focused on identifying each other's evaluative practices and sources of influence on those practices. In addition, schools of nursing can encourage faculty participation in peer development by adopting an expanded view of scholarship in which the disciplined examination of one's evaluative practices is accepted as evidence of the scholarship of teaching.     

Statistical methods for building better biomarkers of chronic kidney disease

The last two decades have witnessed an explosion in research focused on the development and assessment of novel biomarkers for improved prognosis of diseases. As a result, best practice standards guiding biomarker research have undergone extensive development. Currently, there is great interest in the promise of biomarkers to enhance research efforts and clinical practice in the setting of chronic kidney disease, acute kidney injury, and glomerular disease. However, some have questioned whether biomarkers currently add value to the clinical practice of nephrology. The current state of the art pertaining to statistical analyses regarding the use of such measures is critical. In December 2014, the National Institute of Diabetes and Digestive and Kidney Diseases convened a meeting, “Toward Building Better Biomarker Statistical Methodology,” with the goals of summarizing the current best practice recommendations and articulating new directions for methodological research. This report summarizes its conclusions and describes areas that need attention. Suggestions are made regarding metrics that should be commonly reported. We outline the methodological issues related to traditional metrics and considerations in prognostic modeling, including discrimination and case mix, calibration, validation, and cost-benefit analysis. We highlight the approach to improved risk communication and the value of graphical displays. Finally, we address some “new frontiers” in prognostic biomarker research, including the competing risk framework, the use of longitudinal biomarkers, and analyses in distributed research networks.     

The pelvic digit ��eleventh finger��

Described as asymptomatic and an incidental finding on a plain x-ray film, the “pelvic digit” is a rare congenital anomaly. A 35-year-old man is of a rare symptomatic pelvic digit that warranted surgical excision. Its importance lies in its differentiation from acquired abnormalities due to trauma such as myositis ossificans and avulsion injuries of pelvis. If this entity is kept in mind, unnecessary investigations or interventions can be avoided.     

Large-Scale Proteomics and Phosphoproteomics of Urinary Exosomes

Normal human urine contains large numbers of exosomes, which are 40- to 100-nm vesicles that originate as the internal vesicles in multivesicular bodies from every renal epithelial cell type facing the urinary space. Here, we used LC-MS/MS to profile the proteome of human urinary exosomes. Overall, the analysis identified 1132 proteins unambiguously, including 177 that are represented on the Online Mendelian Inheritance in Man database of disease-related genes, suggesting that exosome analysis is a potential approach to discover urinary biomarkers. We extended the proteomic analysis to phosphoproteomic profiling using neutral loss scanning, and this yielded multiple novel phosphorylation sites, including serine-811 in the thiazide-sensitive Na-Cl co-transporter, NCC. To demonstrate the potential use of exosome analysis to identify a genetic renal disease, we carried out immunoblotting of exosomes from urine samples of patients with a clinical diagnosis of Bartter syndrome type I, showing an absence of the sodium-potassium-chloride co-transporter 2, NKCC2. The proteomic data are publicly accessible at http://dir.nhlbi.nih.gov/papers/lkem/exosome/.Urinary exosomes are small extracellular vesicles (<100 nm in diameter) that originate from the internal vesicles of multivesicular bodies (MVB) in renal epithelial cells, including glomerular podocytes, renal tubule cells, and the cells lining the urinary drainage system.¹ Exosomes are released into the urine when the outer membrane of the MVB fuses with the apical plasma membrane of the epithelial cell.Exosomes can be recovered from the urine by differential centrifugation as a low-density membrane fraction. Exosome isolation can result in marked enrichment of low-abundance urinary proteins that have potential pathophysiologic significance. As a consequence, we and others have been working to define optimal conditions for their isolation and purification as a prelude to their use in biomarker discovery studies.^1–3In this study, we thoroughly expanded the known proteome of human urinary exosomes by using a highly sensitive LC-MS/MS system, improved software for identification of peptide ions and a more elaborate data analysis strategy than in our previous study. In addition, we used a neutral loss scanning approach⁴ to investigate the phosphoproteome of human urinary exosomes. The study identified 1412 proteins including 14 phosphoproteins in human urinary exosomes. Overall, there are 177 proteins that are associated with diseases as judged by their presence on the Online Mendelian Inheritance in Man (OMIM) database, 34 of which are known to be associated with renal diseases. The potential clinical usefulness of urinary exosomes was demonstrated using the well-defined renal tubulopathy, Bartter syndrome type I, as an example. The rich information from the proteomic analysis also provides further insight into the biogenesis of urinary exosomes.     

Childhood near‐tetraploid acute lymphoblastic leukemia: an EGIL study on 36 cases

Objectives: Patients with near‐tetraploid (karyotype: 81 – 103 chromosomes) acute lymphoblastic leukemia (NT‐ALL) constitute about 1% of childhood ALL and data reported on them are limited and controversial. The aim of the study was to enlarge the knowledge on these rarely occurring ALL. Methods: The members of the European Group for Immunophenotyping of Leukemias (EGIL) searched retrospectively their databases for NT‐ALL patients. Results: We collected data of 36 European children from seven European countries with NT‐ALL diagnosed since 1992. All patients reached complete remission (CR) after induction chemotherapy. Their blasts were negative for peroxidase and BCR‐ABL1. Ten children were diagnosed as T‐cell ALL (T‐ALL) EGIL categories (T‐I n = 2, T‐II n = 2, T‐III n = 3, T‐IV n = 3) and four displayed various structural chromosomal abnormalities. Eight of 10 T‐ALL remained in 1st CR; one died in CR from sepsis and one is alive in 2nd CR. Median survival was 88 (7–213) months. B‐cell precursor (BCP) ALL was diagnosed in 26 children. Thirteen were positive for ETV6‐RUNX1 and are alive in 1st CR for 32–147 months. Ten children were ETV6‐RUNX1 negative and remained in 1st CR for 16–163 months. One girl with hypodiploid and NT metaphases and ETV6‐RUNX1‐negative BCP‐ALL and one of two boys with NT‐BCP‐ALL not examined for ETV6‐RUNX1 died of infection after stem cell transplantation in 2nd/3rd CR. Secondary myelodysplastic syndrome developed in two patients with NT‐BCP‐ALL. Conclusions: Our data demonstrate immunophenotypic, cytogenetic, and molecular heterogeneity of NT‐ALL and favorable prognosis of most NT‐ALL across different immunophenotypic and/or genetic ALL subtypes.     

Interstitial photodynamic therapy in a rat liver metastasis model.

Photodynamic therapy (PDT) of hepatic tumours has been restricted owing to the preferential retention of photosensitizers in liver tissue. We therefore investigated interstitial tumour illumination as a means of selective PDT. A piece of colon carcinoma CC531 was implanted in the liver of Wag/Rij rats. Photofrin was administered (5 mg kg-1 i.v.) 2 days before laser illumination. Tumours with a mean (+/- s.e.) diameter of 5.7 +/- 0.1 mm (n = 106, 20 days after implantation) were illuminated with 625 nm light, at 200 mW cm-1 from a 0.5 cm cylindrical diffuser and either 100, 200, 400, 800 or 1600 J cm-1. Control groups received either laser illumination only, Photofrin only or diffuser insertion only. Short-term effects were studied on the second day after illumination by light microscopy and computer-assisted integration of the circumference of damaged areas. Long-term effects were studied on day 36. To determine the biochemistry of liver damage and function, serum ASAT and ALAT levels were measured on day 1 and 2, and antipyrine clearance on day 1. Tumour and surrounding liver necrosis increased with light dose delivered (P < 0.001). Best long-term results were obtained at 800 J cm-1 with complete tumour remission in 4 out of 6 animals. No deterioration in liver function was found. The results of this study show the ability of interstitial PDT to cause major destruction of tumour tissue in the liver combined with minimal liver damage.