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The BCL2 inhibitor venetoclax has been approved to treat different hematological malignancies. Because there is no common genetic alteration causing resistance to venetoclax in chronic lymphocytic leukemia (CLL) and B-cell lymphoma, we asked if epigenetic events might be involved in venetoclax resistance. Therefore, we employed whole-exome sequencing, methylated DNA immunoprecipitation sequencing, and genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 screening to investigate venetoclax resistance in aggressive lymphoma and high-risk CLL patients. We identified a regulatory CpG island within the PUMA promoter that is methylated upon venetoclax treatment, mediating PUMA downregulation on transcript and protein level. PUMA expression and sensitivity toward venetoclax can be restored by inhibition of methyltransferases. We can demonstrate that loss of PUMA results in metabolic reprogramming with higher oxidative phosphorylation and adenosine triphosphate production, resembling the metabolic phenotype that is seen upon venetoclax resistance. Although PUMA loss is specific for acquired venetoclax resistance but not for acquired MCL1 resistance and is not seen in CLL patients after chemotherapy-resistance, BAX is essential for sensitivity toward both venetoclax and MCL1 inhibition. As we found loss of BAX in Richter’s syndrome patients after venetoclax failure, we defined BAX-mediated apoptosis to be critical for drug resistance but not for disease progression of CLL into aggressive diffuse large B-cell lymphoma in vivo. A compound screen revealed TRAIL-mediated apoptosis as a target to overcome BAX deficiency. Furthermore, antibody or CAR T cells eliminated venetoclax resistant lymphoma cells, paving a clinically applicable way to overcome venetoclax resistance.

The BCL2 inhibitor venetoclax has been approved to treat different hematological malignancies. Since there is no common genetic alteration causing resistance to venetoclax in CLL and B cell lymphoma, we asked if epigenetic events might be involved in venetoclax resistance. Therefore, we employed whole exome sequencing, methylated DNA immunoprecipitation sequencing and genome wide CRISPR/Cas9 screening to investigate venetoclax resistance in aggressive lymphoma and high-risk CLL patients. We identified a regulatory CpG island within the PUMApromoter which is methylated upon venetoclax treatment, mediating PUMAdownregulation on transcript and protein level. PUMAexpression and sensitivity towards venetoclax can be restored by inhibition of methyltransferases. We can demonstrate that loss of PUMA results in metabolic reprogramming with higher OXPHOS and ATP production, resembling the metabolic phenotype that is seen upon venetoclax resistance. While PUMA loss is specific for acquired venetoclax resistance but not for acquired MCL1 resistance and is not seen in CLL patients after chemotherapy-resistance, BAX is essential for sensitivity towards both venetoclax and MCL1 inhibition. As we found loss of BAX in Richter’s syndrome patients after venetoclax failure, we defined BAX-mediated apoptosis to be critical for drug resistance but not for disease progression of CLL into aggressive DLBCL in vivo. A compound screen revealed TRAIL-mediated apoptosis as a target to overcome BAX deficiency. Furthermore, antibody or CAR T cells eliminated venetoclax resistant lymphoma cells, paving a clinically applicable way to overcome venetoclax resistance.

A survey was posted to all New South Wales and Provisional Fellows of the Australian and New Zealand College of Anaesthetists to assess the influence of the current medicolegal climate on their anaesthetic practice. Information collected included demographics, opinions regarding the current medico-legal climate, medical defence organizations, and the implications for anaesthetic practice. The response rate was 78% (640/820). Nearly all (95.3%) were concerned about the current medical indemnity crisis and 80.5% felt concerned about the financial security of medical insurers. Of all these respondents 23.6% had personal experience of litigation and 73.6% expected to have a claim made against them during their career. Respondents spent an average of 8.3% of their gross annual income on medical insurance premiums and 47.2% are concerned about the viability of their practice given the rising costs of medical insurance. Obstetric anaesthesia was the most common area of practice to be ceased due to medicolegal concerns. In the next two years, 20.2% of obstetric anaesthetists who responded intend to cease practice. In the past two years, 3.1% of respondents retired due to their litigation concerns, while 12.8% (average age 56.7y) are intending to retire in the next two years for the same reasons. Changes to the conduct of the preoperative consultation were common. Other changes to practice included more thorough documentation of complications (50.8%) and a strong reluctance to perform neuraxial blocks (54%). This survey suggests that anaesthetists are concerned about the current medicolegal climate and as a result, some are retiring earlier and giving up high-risk areas of practice.

Starting from the optical properties of laser beams, the requirements of optical systems for manipulating laser radiation in industrial applications are derived. The relevant parameters, relations to the diffraction limit and the state-of-the-art design techniques are discussed. The three important types of lasers for use in industrial materials processing operate at wavelengths ranging from the infrared (10.6 µm, CO2 laser; 1.06 µm, Nd:YAG) to the ultraviolet region (excimer lasers). Each wavelength range is associated with specific design challenges. The scarcity of suitable refractive materials for the 10 µm wavelength range and the ultraviolet below 300 nm is a major constraint. Reflective systems are used widely at the longer wavelength, but some designs suffer from coma. The 1.06 µm radiation from the Nd:YAG laser can make use of many well-developed optical means for handling visible light. Energy transport by optical fibres is commonly used. Optical systems for excimer laser applications are specific in that they image a mask onto a workpiece, and use the high photon energy and the high definition possible with the short wavelength for precision micro-machining.

Remedial action at an industrial site contaminated with chlorinated organic compounds including PCDD/PCDF involves thermal treatment of soil to reduce levels of 2,3,7,8-TCDD below a target value of 60 ng/kg. To guarantee the required quick turnaround for the analyses, a problem-oriented method was developed for the selective determination of 2,3,7,8-TCDD on a time scale of 2 – 4 h. Treated soil is extracted with an acidic solvent mixture (ethoxyethanol/toluene/6 mol/l sulphuric acid). The 2,3,7,8-TCDD in the extract is separated from matrix components and other PCDD/PCDF congeners by flash chromatography on alumina. The selectivity attained in this step allows final determination using isotope dilution GC/MS on a non-polar column. The method is in routine operation in an on-site laboratory. With a bench top quadrupole instrument, detection limits around 3 – 5 ng/kg are obtained.

Summary: SDMinP is an easy-to-use program for fast calculation of empirical and adjusted P-values for correlated and uncorrelated hypotheses in multiple testing experiments. It is based on the Free Step-Down Resampling Method for controlling the family wise error rate, and implements a variation of an efficient algorithm, which reduces the originally required re-sampling effort considerably and makes the method computationally feasible. The program is independent of the underlying test statistic and works with provided observed and permutation test statistics. Availability: http://www.dkfz.de/SDMinP/software.html Contact: L.beckmann@dkfz.de