Bioimpedance spectroscopy is not associated with a clinical diagnosis of breast cancer-related lymphedema.

The objective of this study was to evaluate the accuracy of bioimpedance spectroscopy measurements (L-Dex) in the diagnosis of breast cancer-related lymphedema. A retrospective review of a prospectively maintained database was performed of all patients that underwent surgical treatment for breast cancer at a tertiary medical center. Patients who had preoperative and postoperative evaluation for possible lymphedema by limb circumference measurements and bioimpedance were eligible for inclusion in the study. No significant demographic differences were found between the group of patients clinically diagnosed with lymphedema (N=134) and those without a clinical diagnosis of lymphedema (N=261). The ability of bioimpedance to diagnose lymphedema based on the manufacturer's criteria demonstrated low sensitivity, which was 7.5% when lymphedema was defined as an absolute L-Dex value greater than 10, and 24.6% when defined as a relative change of >10 between preoperative and postoperative measurements. This corresponded with a positive predictive value of 61-71% and a negative predictive value of 67-70%. We are unable to recommend the use of bioimpedance as a screening tool or for measurement of breast cancer-related lymphedema.

A non-invasive fluorescent staining procedure allows Confocal Laser Scanning Microscopy based imaging of Mycobacterium in multispecies biofilms colonizing and degrading polycyclic aromatic hydrocarbons.

To study the micro scale interactions of Mycobacterium with bacteria belonging to other genera by means of Confocal Laser Scanning Microscopy (CLSM), a procedure was developed to non-invasively and fluorescently stain Mycobacterium without compromising the signal produced by commonly used fluorescent reporter genes. The procedure makes use of the commercial non-specific nucleic acid stain Syto62 and was optimized to efficiently stain Mycobacterium cells in suspensions and biofilms. The staining procedure was found non-invasive towards overall cell viability, biofilm architecture and fluorescence signals emitted by other organisms expressing the fluorescent reporter genes gfp and dsRed. The procedure was successfully applied to visualize the comportment of the PAH-degrading Mycobacterium sp. VM552 in triple species biofilms containing, in addition to strain VM552, the GFP labeled PAH-degrading Sphingomonas sp. LH128-GFP and DsRed-labeled Pseudomonas putida OUS82(RF), and colonizing a glass substrate coated with phenanthrene crystals in flow chambers. CLSM imaging and subsequent appropriate image processing of the biofilms show that the comportment of strain Mycobacterium sp. VM552 was largely affected by the presence of the other organisms. The data support the value of the staining procedure to study ecological questions about micro scale behavior and niche occupation of Mycobacterium in multi-species systems.

Scanning-less wide-field single-photon counting device for fluorescence intensity, lifetime and time-resolved anisotropy imaging microscopy.

A scanning-less single-photon counting system for FLIM and fluorescence anisotropy wide-field imaging is described and characterized in this paper. The two polarizations of the fluorescence are divided by a Glan prism and acquired at the same time by the Q(A) detector. Fluorescence decay profiles can be reconstructed for any desired area up to each pixel and used to calculate time-resolved fluorescence anisotropy decays.

Experiments with a programmable master hearing aid.

A series of experiments is described tracing the development and application of adaptive paired-comparison testing to the prescriptive fitting of hearing aids. The equipment needed to implement the test procedures became progressively more complex with each new experiment, leading to the development of a digital master hearing aid.