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Advances in diagnostic technologies enabled scientists to link a large number of diseases with structural changes of the intracellular organisation. This intrinsic biophysical characteristic opened up the possibility to perform clinical assessments based on the measurement of single-cell mechanical properties. In this work, we combine microfluidics, high speed imaging and computational automatic tracking to measure the single-cell deformability of large samples of prostate cancer cells at a rate of ~ 10 4 cells/s . Such a high throughput accounts for the inherent heterogeneity of biological samples and enabled us to extract statistically meaningful signatures from each cell population. In addition, using our technique we investigate the effect of Latrunculin A to the cellular stiffness.

Diseases of urinary bladder are a common healthcare problem world over. Diagnostic precision and predicting response to treatment are major issues. This study aims to create an optical cross-sectionional model of a bladder, capable of visually representing the passage of photons through the tissue layers. The absorption, transmission and reflectance data, along with the derived transmission coefficients (of scattering and absorption) were obtained from literature analysis and were used in the creation of a “generic” cross-section optical property model simulating the passage of thousands of photons through the tissue at different wavelengths. Fluorescence spectra of diagnostically relevant biomarkers excited by the UV and blue wavelengths were modelled on the basis of the Monte-Carlo method. Further to this, fluorescence data gathered by the “LAKK-M” system from pig bladders was applied to the model for a specific representation of the photon passage through the tissues. The ultimate goal of this study is to employ this model to simulate the effects of different laser wavelength and energy inputs to bladder tissue and to determine the effectiveness of potential photonics based devices for the diagnosis of bladder pathologies. The model will aid in observing differences between healthy and pathological bladder tissues registered by photonics based devices.

Bladder cancer is among the most common cancers worldwide (4th in men). It is responsible for high patient morbidity and displays rapid recurrence and progression. Lack of sensitivity of gold standard techniques (white light cystoscopy, voided urine cytology) means many early treatable cases are missed. The result is a large number of advanced cases of bladder cancer which require extensive treatment and monitoring. For this reason, bladder cancer is the single most expensive cancer to treat on a per patient basis. In recent years, autofluorescence spectroscopy has begun to shed light into disease research. Of particular interest in cancer research are the fluorescent metabolic cofactors NADH and FAD. Early in tumour development, cancer cells often undergo a metabolic shift (the Warburg effect) resulting in increased NADH. The ratio of NADH to FAD ("redox ratio") can therefore be used as an indicator of the metabolic status of cells. Redox ratio measurements have been used to differentiate between healthy and cancer breast cells and to monitor cellular responses to therapies. Here, we have demonstrated, using healthy and bladder cancer cell lines, a statistically significant difference in the redox ratio of bladder cancer cells, indicative of a metabolic shift. To do this we customised a standard flow cytometer to excite and record fluorescence specifically from NADH and FAD, along with a method for automatically calculating the redox ratio of individual cells within large populations. These results could inform the design of novel probes and screening systems for the early detection of bladder cancer.

Multi-functional laser non-invasive diagnostic systems, such as “LAKK-M”, allow the study of a number of microcirculatory parameters, including blood microcirculatory index (Im) (by laser Doppler flowmetry, LDF) and oxygen saturation (StO2) of skin tissue (by tissue reflectance oximetry, TRO). Such systems may provide significant information relevant to physiology and clinical medicine. The aim of this research was to use such a system to study the synchronization of microvascular blood flow and oxygen saturation rhythms under normal and adaptive change conditions. Studies were conducted with 8 healthy volunteers – 3 females and 5 males of 21-49 years. Each volunteer was subjected to basic 3 minute tests. The volunteers were observed for between 1-4 months each, totalling 422 basic tests. Measurements were performed on the palmar surface of the right middle finger and the forearm medial surface. Wavelet analysis was used to study rhythmic oscillations in LDF- and TRO-data. Tissue oxygen consumption (from arterial and venal blood oxygen saturation and nutritive flux volume) was calculated for all volunteers during “adaptive changes” as (617±123 AU) and (102±38 AU) with and without arteriovenous anastomoses (AVAs) respectively. This demonstrates increased consumption compared to normal (495±170 AU) and (69±40 AU) with and without AVAs respectively. Data analysis demonstrated the emergence of resonance and synchronization of rhythms of microvascular blood flow and oxygen saturation as an adaptive change in myogenic oscillation (vasomotion) resulting from exercise and potentially from psychoemotional stress. Synchronization of myogenic rhythms during adaptive changes suggest increased oxygen consumption resulting from increased microvascular blood flow velocity.