Automated measurement of MIB-1 positive area as an alternative to counting in follicular lymphoma.

Manual counting of MIB-1 positive cells which has been suggested as an alternative to centroblast counting for the diagnostic grading of follicular lymphoma is a laborious task. In this study, the validity of automated measurement of the MIB-1 positive area is analyzed as an alternative approach. Archival MIB-1 stained tissue sections of 15 follicular lymphomas were assessed manually and automatically by three independent observers. Concordance correlation coefficients and coefficients of variation were calculated to study reproducibility and variability of both methods and to compare result from both methods. A good concordance was observed between the two methods. The reproducibility of the automated method was slightly better than the manual counting of positive nuclei. Measurement of MIB-1 positive surface area may be used as a simple and fast alternative to tedious manual counting of positive nuclei as a potential help in follicular lymphoma grading.

Changes in Work Practices for Safe Use of Formaldehyde in a University-Based Anatomy Teaching and Research Facility.

Anatomy teaching and research relies on the use of formaldehyde (FA) as a preservation agent for human and animal tissues. Due to the recent classification of FA as a carcinogen, university hospitals are facing a challenge to (further) reduce exposure to FA. The aim of this study was to reduce exposure to FA in the anatomy teaching and research facility. Workers participated in the development of improved work practices, both technical and organizational solutions. Over a period of 6 years mitigating measures were introduced, including improvement of a down-flow ventilation system, introduction of local exhaust ventilation, collection of drain liquid from displayed specimens in closed containers and leak prevention. Furthermore, some organizational changes were made to reduce the number of FA peak exposures. Stationary and personal air sampling was performed in three different campaigns to assess the effect of these new work practices on inhalation exposure to FA. Samples were collected over 8 h (full shift) and 15 min (task-based) to support mitigation of exposure and improvement of work practices. Air was collected on an adsorbent coated with 2,4-dinitrophenylhydrazine (DNPH) and analyzed by HPLC-UV. Geometric mean (GM) concentrations of FA in the breathing zone over a work-shift were 123 µg/m³ in 2012 and 114 µg/m³ in 2014, exceeding the workplace standard of 150 µg/m³ (8 h time-weighted average, TWA) on 46% of the workdays in 2012 and 38% of the workdays in 2014. This exposure was reduced to an average of 28.8 µg/m³ in 2017 with an estimated probability of exceeding the OEL of 0.6%. Task-based measurements resulted in a mean peak exposures of 291 µg/m³ in 2012 (n = 19) and a mean of 272 µg/m³ in 2014 (n = 21), occasionally exceeding the standard of 500 µg/m³ (15 min TWA), and were reduced to a mean of 88.7 µg/m³ in 2017 (n = 12) with an estimated probability of exceeding the OEL of 1.6%.