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This paper reports on the biospeckle processing of biological activity using a visualization scheme based upon the digital imaging information technology. Activity relative to bacterial growth in agar plates and to parasites affected by a drug is monitored via the speckle patterns generated by a coherent source incident on the microorganisms. We present experimental results to demonstrate the potential application of this methodology for following the activity in time. The digital imaging information technology is an alternative visualization enabling the study of speckle dynamics, which is correlated to the activity of bacteria and parasites. In this method, the changes in Red-Green-Blue (RGB) color component density are considered as markers of the growth of bacteria and parasites motility in presence of a drug. The RGB data was used to generate a two-dimensional surface plot allowing an analysis of color distribution on the speckle images. The proposed visualization is compared to the outcomes of the generalized differences and the temporal difference. A quantification of the activity is performed using a parameterization of the temporal difference method. The adopted digital image processing technique has been found suitable to monitor motility and morphological changes in the bacterial population over time and to detect and distinguish a short term drug action on parasites.

This paper reports on the application of the motion history image (MHI) method on dynamic laser speckle processing as a result of a specific drug action on Trypanosoma cruzi parasites. The MHI procedure is based on human action recognition, and unlike other methods which use a sequence consisting of several frames for recognition, this method uses only an MHI per action sequence for recognition. MHI method avoids the complexity as well as the large computation in sequence matching-based methods and detects a change in the speckle pattern. Experimental results of MHI on real-time monitoring of activity (motility) under the influence of the drug demonstrate the effectiveness of the proposed method. The MHI showed an online result without loss of resolution and definition if we compare with routine LASCA method. The obtained results highlight the advantage of the MHI analysis over traditional qualitative image intensity-based methods and demonstrate the potential of measuring the activity of parasites via dynamic laser speckle analysis. The data was further numerically analyzed in the time domain, and the results presented the ability of the technique to monitor the action of the drug, particularly Epirubicin (100 μg/ml).

In this paper, we report on a biospeckle laser method used to monitor a specific drug action on T. cruzi parasites. Experimental results from fast biospeckle monitoring of the parasites' activity under the influence of the drug demonstrate the effectiveness of the proposed method. We measure the speckle parameters such as spatiotemporal correlation and speckle grain size to assess the immediate action of the drug on the parasites during a very short incubation period. From a practical point of view, this aproach allows us to validate biospeckle as a fast, non-invasive and alternative method to test candidate drugs on T. cruzi parasites.