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Conference 11959
Dynamics and Fluctuations in Biomedical Photonics XIX
22 - 23 January 2022 | Room 154 (Upper Mezzanine South)
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Presentation times are finalized; please adhere to the schedule
Session 1:
Optical Coherence Tomography
22 January 2022 • 10:30 AM - 11:00 AM PST | Room 154 (Upper Mezzanine South)
Session Chair:
Ruikang K. Wang, Univ. of Washington (United States)
11959-2
Tracking spermatozoa movement toward the egg with functional optical coherence tomography
(Invited Paper)
22 January 2022 • 10:30 AM - 11:00 AM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
Fertilization is a critical reproductive step combining two gametes from parents, the egg and the sperm. This process is complex and highly dynamic. In-vivo visualization of mammalian fertilization is highly desired but has not been achieved yet. Toward this goal, this study presents the development of the speckle variance (SV) optical coherence tomography (OCT) analysis for volumetric tracking of sperm migration through the cumulus matrix toward the oocyte in vitro. Potentially, this method will be integrated with intravital OCT imaging to capture the process of mammalian fertilization in vivo.
Session 2:
Tissue and Cell Dynamics at Micro and Nano Scale
22 January 2022 • 11:00 AM - 11:50 AM PST | Room 154 (Upper Mezzanine South)
Session Chair:
Ruikang K. Wang, Univ. of Washington (United States)
11959-6
Effect of localized ablative immunotherapy on transcriptomic regulations in breast tumor-infiltrating dendritic cells
(Invited Paper)
22 January 2022 • 11:00 AM - 11:30 AM PST | Room 154 (Upper Mezzanine South)
11959-8
22 January 2022 • 11:30 AM - 11:50 AM PST | Room 154 (Upper Mezzanine South)
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A biofilm morphology transition is a dynamic process that mediates growth and dispersion. The development of the dynamic process shows the enhancement of the power-law tail that is observed while the biofilms grown at the air-agar interface are submerged in a medium. Environmentally driven morphology transitions of biofilm were analyzed by acquiring the phase displacements of the Doppler shift and linearly decomposed by ballistic (Cauchy) and diffusive (Gaussian) distributions. The analysis provides the internal dynamic characteristics of biofilm that pave the way between the conventional dynamic parameters and the anomalous diffusion parameters.
Break
Lunch/Exhibition Break 11:50 AM - 1:00 PM
Session 3:
Laser Speckle Techniques
22 January 2022 • 1:00 PM - 2:20 PM PST | Room 154 (Upper Mezzanine South)
Session Chair:
Ruikang K. Wang, Univ. of Washington (United States)
11959-10
Simulation of statistically accurate time-integrated dynamic speckle patterns in biomedical optics
(Invited Paper)
22 January 2022 • 1:00 PM - 1:30 PM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
The simulation of statistically accurate time-integrated dynamic speckle patterns using a physics-based model that accounts for spatially varying sample properties is yet to be presented in biomedical optics. In this work, we propose a solution to this important problem based on the Karhunen-Loève expansion of the electric field, and apply our method to the formalisms of both laser speckle contrast imaging and diffuse correlation spectroscopy. We validate our technique against solutions for speckle contrast for different forms of homogeneous field, and also show that our method can readily be extended to cases with spatially varying sample properties.
11959-11
Poincaré descriptors for speckle statistics and dynamics
(Invited Paper)
22 January 2022 • 1:30 PM - 2:00 PM PST | Room 154 (Upper Mezzanine South)
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New descriptors of speckle statistics and dynamics are presented that link short-term and long-term variation in the imaged speckle to the motions present in the object. The approach yields images that resemble LSCI images, however instead of relying upon the statistics of the local time integrated intensity values, the approach directly yields images that quantify the relative dominance of long-range correlations over the short-range correlations. A similar approach can be employed on a single speckle image to describe the second-order statistics of the speckle pattern. Details of this approach along with applications to tissue dynamics and thermal measurements will be presented.
11959-13
22 January 2022 • 2:00 PM - 2:20 PM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
We propose an analytical-numerical model based on the optical Doppler effect for handheld laser speckle contrast imaging (LSCI) in case of translation on a high scattering static surface. The model incorporates the type of illumination as well as the imaging geometry by taking into account the spread of wavevectors for illumination and detection. We validate the theoretical model by simulated dynamic speckles and experiments. Results of the speckle simulation are in agreement with predictions of the numerical model for semi-circular form of the density functions of the incoming and outgoing wavevectors.
Session 4:
Spectroscopy and Applications
22 January 2022 • 2:20 PM - 3:20 PM PST | Room 154 (Upper Mezzanine South)
Session Chair:
Ruikang K. Wang, Univ. of Washington (United States)
11959-16
22 January 2022 • 2:20 PM - 2:40 PM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
We have previously demonstrated a novel Fourier domain diffuse correlation spectroscopy instrument that makes use of holographic camera-based detection, and which is capable of making in vivo pulsatile flow measurements. In this work, we detail considerations to further characterise the signal-to-noise ratio performance of our system. These include demonstration and elimination of laser multimode behaviour, and correction for the camera's modulation transfer function to ensure faithful reconstruction of measured intensity profiles. We document the effect of varying laser source power, and also demonstrate a technique to remove spatiotemporally correlated noise sources to reveal the performance limit of our instrument.
11959-18
22 January 2022 • 2:40 PM - 3:00 PM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
Tissue dynamics spectroscopy (TDS) uses coherence-gated dynamic light scattering from living tissues to predict tissue response to applied drugs. In clinical trials aimed at measuring patient chemoresistance, intra-sample variability poses a challenge for the prediction of patient response to therapy. Previous work has identified and characterized different baseline conditions and drug responses by averaging TDS signatures over patient biopsies, but most samples display more than one phenotypic response to the treatment. To address this problem, we introduce well-by-well phenotypic classification to improve chemoresistance accuracy. The methodology is applied here to a recently-concluded clinical trial measuring TDS of human esophageal cancer.
11959-20
22 January 2022 • 3:00 PM - 3:20 PM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
We developed and applied parallel interferometric near-infrared spectroscopy (πNIRS) to noninvasively monitor pulsatile blood flow deep into the human tissue in vivo. With the unique capability of accessing complex information (amplitude and phase) about the sample with more than 1000 parallel channels, we can sense blood flow with only 20 ms integration time, making the πNIRS one of the fastest and comprehensive diffuse optical method.
BiOS Hot Topics
22 January 2022 • 7:00 PM - 9:00 PM PST | Room 207/215 (Level 2 South)
Session 5:
Functional Imaging and Evaluations
23 January 2022 • 9:30 AM - 11:50 AM PST | Room 154 (Upper Mezzanine South)
Session Chair:
Ruikang K. Wang, Univ. of Washington (United States)
11959-22
23 January 2022 • 9:30 AM - 10:00 AM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
The autocorrelation-based optical coherence tomography motility metric (OCT M) is sensitive to intracellular motion and independent of shot noise. M is widely applied to quantify drug and toxicant responses in 3D tissue models. To improve data scanning and storage efficiency, we propose a temporally uneven compressed sensing method to estimate short- and long-time correlations from OCT data. First, simulated OCT signals assuming diffusive motion demonstrates the method and its limitations. Then, M values derived from OCT data in mammary epithelial cell spheroids exposed to estrogen demonstrate that compressed M accurately reconstructs uncompressed M values at up to 8x compression ratio.
11959-23
23 January 2022 • 10:00 AM - 10:20 AM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
In pulse oximetry, arterial oxygen saturation (SpO2) is calculated from near-infrared spectroscopy (NIRS) data using the modified Beer-Lambert Law. Tissue homogeneity is assumed, and the photon mean pathlength (〈L〉) needs to be known or calibrated for. We aim to develop a transabdominal fetal pulse oximeter, where SpO2 = 40-70% and the homogeneity assumption and experimental calibration cannot be applied. Our approach relies on spectral fitting of normalized 〈L〉 from NIRS measurements with analytical description of 〈L〉. Data from simulations and human subjects are presented. Our preliminary results show that the self-calibrated algorithm can accurately extract SpO2 changes in homogenous tissue.
Coffee Break 10:20 AM - 10:50 AM
11959-24
23 January 2022 • 10:50 AM - 11:10 AM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
Ovulation is essential for mammalian reproduction. The aim of this study was to investigate how ovulated eggs are transported within the ovarian bursa to the infundibulum. We utilized optical coherence tomography (OCT) for dynamic imaging of ovulatory processes in mice. The OCT imaging enabled spatio-temporal analysis of the eggs in the ovarian bursa, and indicated that the periodic movement of the bursa could contribute to the egg transport. This study demonstrates intravital optical coherence tomography as a promising tool for in vivo analysis of mammalian ovulation and suggests potential mechanisms for the egg transport to the infundibulum.
11959-25
23 January 2022 • 11:10 AM - 11:30 AM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
Spermatozoa motility is critical for successfully reaching the egg and fertilization. One of essential transitions in sperm behavior within the female reproductive tract required for fertilization is hyperactivation. Our group established an innovative volumetric in vivo sperm tracking approach using OCT through an intravital imaging window. This study is focused on the development of new functional OCT quantitative measures for the analysis of sperm hyperactivation state. The quantitative parameters were first developed in vitro; then optimized and tested in vivo. This work established a potential quantitative approach for differentiating sperm hyperactivation status based on their trajectories in vivo.
11959-26
23 January 2022 • 11:30 AM - 11:50 AM PST | Room 154 (Upper Mezzanine South)
Show Abstract +
We assessed impairments of cerebral microcirculation in cardiac cessation and respiratory arrest. The LSCI revealed a reduction of cerebral blood flow in small and medium vessels during first minutes of respiratory arrest as well as in large sinuses in cardiac arrest. The redox ratio measured by FS indicated a progressing hypoxia, NADH accumulation, FAD consumption increase. DRS measurements exposed a rapid perfusion grow in deoxygenated blood in cardiac impairments. A histopathological analysis demonstrated a higher neuronal wrinkling in cardiac impair. In respiratory arrest we found focal perivascular edema and mild hypoxic changes. The results showed circulatory to be more dramatic in a cardiac arrest.
Posters-Sunday
23 January 2022 • 5:30 PM - 7:00 PM PST | Moscone West, Lobby (Level 3)
Conference attendees are invited to attend the Sunday BiOS poster session. Come view the posters, enjoy light refreshments, ask questions, and network with colleagues in your field.
Poster Setup: Sunday 12:00 PM – 5:00 PM
View poster presentation guidelines and set-up instructions at:
https://spie.org/PW/Poster-Guidelines
Poster Setup: Sunday 12:00 PM – 5:00 PM
View poster presentation guidelines and set-up instructions at:
https://spie.org/PW/Poster-Guidelines
11959-33
23 January 2022 • 5:30 PM - 7:00 PM PST | Moscone West, Lobby (Level 3)
Show Abstract +
The present work demonstrates the assessment of cytotoxicity upconversion nanoparticles (UCNPs) coated by SiO2 on different normal and cancer murine cell lines in vitro. The cell viability is scored for cytotoxic effects of UCNPs at dark conditions. UCNPs coated by silica shells provide a dose-dependent cytotoxic effect on all studied cell lines which was most pronounced for the Raw264.7 cell line. It is probably caused by the high phagocytic activity of macrophages. The less sensitive cell line was 4T1. The statistically significant differences in cell viability after 24 and 48 h of incubation of cells with particles were observed just for the macrophage cell line. It is worth notifying that after 48 h of incubation the cytotoxic effect on Raw 264.7 cell line increased which shows a possible negative effect on some subpopulations on blood cells. The obtained results confirm a high sensitivity of the UCNPs to the concentration variations within cells. Carriers based on UCNPs and dyes are promising alternatives to photosensitizer for traditional photodynamic therapy and possess prominent potentials in biological and clinical applications.
Conference Chair
Saratov State Univ. (Russian Federation), Tomsk State Univ. (Russian Federation), Institute of Precision Mechanics and Control of the RAS (Russian Federation)
Program Committee
Brendan F. Kennedy
The Univ. of Western Australia (Australia)
Program Committee
Vesa Kiviniemi
Univ. of Oulu (Finland)
Program Committee
Teemu S. Myllylä
Univ. of Oulu (Finland)