A new, inexpensive method is described that enables lymphocytes to be enumerated very precisely. Normal leukocytes were simultaneously stained and fixed with a propidium iodide-paraformaldehyde solution. The preparation obtained (CellBeads) was used as an internal standard for cell enumeration by flow cytometry and was stable at 4°C for at least 60 days. Unlike synthetic beads, the CellBeads behaved similarly to normal cells during red blood cell lysis and cell washing procedures. When known numbers of CellBeads were added to whole-blood samples and the numbers of CellBeads and lymphocytes were determined, highly reproducible and accurate enumerations were obtained-far more so than when synthetic beads were used. This inexpensive method is suitable for routine use.There is often a requirement for cells of a specific type to be accurately enumerated in absolute numbers per unit volume. For example, enumeration of CD4 ϩ T lymphocytes is essential in the evaluation of prognosis and therapy in patients infected with human immunodeficiency virus (HIV) (9), and enumeration of CD34 ϩ stem cells is important in the assessment of cancer patients receiving stem cell transplantation (3).There are currently two ways of enumerating such cells. The dual-platform method calculates absolute cell numbers from the relative frequency of phenotypes (derived from a flow cytometer) and the total white blood cell (WBC) count (derived from a hematology analyzer). Unfortunately, this approach leads to great interlaboratory variation in estimation of CD4 ϩ lymphocyte counts (3) because of errors inherent in WBC enumeration by hematology analyzers.The single-platform method does not involve a hematology analyzer, using only a flow cytometer. It is more precise as it relies on either concomitant precise measurement of the fluid volume in which such suspended cells are enumerated or the precise addition of fluorescent calibration particles to the sample. While a new generation of flow cytometers with precision fluidics may represent the long-term solution to problems of interlaboratory variation, most laboratories still rely on flow cytometers that lack the ability to measure fluid volumes precisely.Manufacturers of flow cytometers market systems of beads, protocols, and software that purport to provide precise enumeration, e.g., the PROCOUNT system from Becton Dickinson (2) or Flow-Count Fluorospheres from Beckman Coulter. However, assays using such commercially available beads are expensive (around an additional $6/test for the TruCount system or an additional $1.6/test for Fluorospheres), and this may be beyond the means of some laboratories. Other commercially available fluorescent beads are designed primarily for calibration of flow cytometers rather than enumeration of cells in individual samples. These beads, usually plastic, are not suitable for the latter purpose. Many experiments performed by us (results not shown) daily over the course of 3 months, produced data with very poor reproducibility, large variation, and major inaccurac...

This study confirms that a staging BS can be safely avoided in patients with intermediate-risk prostate cancer with Gleason primary pattern 3 and to limit performing BS in all high-risk prostate cancer and in the intermediate-risk group when the primary Gleason pattern is 4, thereby reinforcing the current recommendations of the EAU guidelines.

This paper analyses the Trade and Cooperation Agreement (TCA) between the EU and the UK. We focus on two specific features: rules of origin and non-tariff barriers. The putative purpose of the TCA was to promote free trade between the signatories, and both of the features identified have ‘level-playing-field’ objectives which are designed to promote that purpose. However, both can also be used for covert protectionism against the other party to the agreement. The paper recommends that rules of origin and non-tariff barriers should be recrafted where possible, and there is a description of how this might be done. The aim of such action would be to make transparent the role of these features in preserving a level playing field. Doing this would also make clear that any residual unadulterated rules of origin and non-tariff barriers existed for purely protectionist reasons and jeopardized open borders. Hopefully, the exposure of such protectionism would encourage its dismantlement.

Lower urinary tract symptoms in men are common, increase with age and can become bothersome, causing significant morbidity such as urinary retention or the need for surgery. This article outlines how to assess a man with lower urinary tract symptoms and when to refer to a specialist, and summarizes current treatment options.