Motility Patterns Research Articles

Production and Evaluation of Frozen Semen of Sahiwal Bull Using Two Different Diluters and Protocols

The experiment was designed to evaluate the effects of diluters and freezing protocols on frozen semen production of Sahiwal breeding bulls. Imported 100% Sahiwal breeding bulls were then reared in the American dairy limited (ADL). Semen samples are processed and frozen once a week in the ADL. Spermatozoa with various motility patterns were collected; these included post-thawing, progressive, fast, slow, circular, and local. Computer Assisted Semen Analyzer (CASA) was used to measure the straight-line velocity (VSL), curvilinear velocity (VCL) and linearity (LIN) parameters. Two diluters (tris egg-yolk and tris egg-yolk aqua) and freezing protocols (slow freezing and fast freezing) were used for frozen semen production of these bulls. The significantly highest (P<0.05) number of post-thawing total, progressive and progressive fast motility (78.42±1.88, 73.50±1.90 and 59.68±2.10%), VCL (115.31±3.82µm/s) and lowest slow, circular and local motility (13.44±1.40, 0.57±0.08 and 4.92±0.41%), LIN (0.39±0.01%) was found in diluter 1 and freezing protocol 2. On the other hand, highest number of circular motility (0.77±0.18%) and VSL (44.83±1.17µm/s) was found in diluter 1 and freezing protocol 1 whereas highest number of slow and local motility (18.84±1.23 and 7.46±0.57%) and LIN (0.61±0.20%) and lowest progressive fast motility (48.73±2.28%), VCL (98.90±3.42µm/s), VSL (39.76±1.33µm/s) was found in diluter 2 freezing protocol 2 and also lowest post-thawing and progressive motility (73.44±1.94 and 66.51±2.02%) was observed in diluter 2 freezing protocol 1. The study reveals that diluter 1(one step egg yolk based) and freezing protocol 1 (5 steps) and 2 (2 steps) seems to be an efficient method for frozen semen production.

Role of motility and nutrient availability in drying patterns of algal droplets.

Sessile drying droplets in various bio-related systems attracted attention due to the complex interactions between convective flows, droplet pinning, mechanical stress, wettability, and the emergence of unique patterns. This study focuses on the drying dynamics of Chlamydomonas reinhardtii (chlamys), a versatile model algae used in molecular biology and biotechnology. The experimental findings shed light on how motility and nutrient availability influence morphological patterns- a fusion of macroscopic fluid dynamics and microbiology. This paper further discusses the interplay of two competing stressors during drying- nutrient scarcity (quantitative analysis) and mechanical stress (qualitative analysis), where the global mechanical stress does not induce cracks. Interestingly, motile chlamys form clusters under nutrient scarcity due to metabolic stress, indicating the onset of flocculation, a common feature observed in microbial systems. Moreover, non-motile chlamys exhibit an "anomalous coffee-ring effect" in the presence of nutrients, with an inward movement observed near the droplet edge despite sufficient water in the droplet. The quantitative image processing techniques provide fundamental insights into these behaviors in classifying the patterns into four categories (motile+with nutrients, motile+without nutrients, non-motile+with nutrients, and non-motile+without nutrients) across five distinct drying stages- Droplet Deposition, Capillary Flow, Dynamic Droplet Phase, Aggregation Phase, and Dried Morphology.

Profiling Dynamic Patterns of Single-Cell Motility.

Cell motility plays an essential role in many biological processes as cells move and interact within their local microenvironments. Current methods for quantifying cell motility typically involve tracking individual cells over time, but the results are often presented as averaged values across cell populations. While informative, these ensemble approaches have limitations in assessing cellular heterogeneity and identifying generalizable patterns of single-cell behaviors, at baseline and in response to perturbations. In this study, CaMI is introduced, a computational framework designed to leverage the single-cell nature of motility data. CaMI identifies and classifies distinct spatio-temporal behaviors of individual cells, enabling robust classification of single-cell motility patterns in a large dataset (n = 74253 cells). This framework allows quantification of spatial and temporal heterogeneities, determination of single-cell motility behaviors across various biological conditions and provides a visualization scheme for direct interpretation of dynamic cell behaviors. Importantly, CaMI reveals insights that conventional cell motility analyses may overlook, showcasing its utility in uncovering robust biological insights. Together, a multivariate framework is presented to classify emergent patterns of single-cell motility, emphasizing the critical role of cellular heterogeneity in shaping cell behaviors across populations.

Unravelling a diversity of cellular structures and aggregation dynamics during the early development of Myxococcus xanthus.

Aggregation underlies the collective dynamics of a diversity of organisms, enabling the formation of complex structures and emergent behaviours on interaction with the environment. Cellular aggregation constitutes one of the routes to collective motility and multicellular development. Myxococcus xanthus, a social bacterium, is a valuable model for studying the aggregative path to multicellularity, a major transition in the evolutionary history of life. While the collective developmental behaviour of M. xanthus has been largely studied in high cellular densities, there is a lack of understanding at low-density conditions that can be ecologically relevant. In this work, we study the early stages of emergent collective behaviour of M. xanthus under nutrient-poor and low-density conditions, uncovering the formation of diverse cellular structures with different shapes and sizes, ranging from individual cells to networks comprising thousands of cells. We study their motility patterns and their prevalence along development and discuss their cross-scale role on the population's exploratory dynamics. This work contributes to understanding key, yet largely understudied, aspects in the early stages of multicellular development in myxobacteria, shedding light on the dynamics underlying aggregative processes in this and other taxa and study systems.

S813 Artificial Intelligence as a Transforming Factor in Motility Disorders - Automatic Detection and Differentiation of Motility Patterns in High-Resolution Anorectal Manometry

S813 Artificial Intelligence as a Transforming Factor in Motility Disorders - Automatic Detection and Differentiation of Motility Patterns in High-Resolution Anorectal Manometry

S645 Esophageal Motility Patterns in Patients Receiving GLP-1RA Therapy

S645 Esophageal Motility Patterns in Patients Receiving GLP-1RA Therapy

Effect of Thawing Procedure and Thermo-Resistance Test on Sperm Motility and Kinematics Patterns in Two Bovine Breeds.

This investigation aimed to analyze the effect that thawing time and temperature in combination with a termo-resistance test had on straws from dairy bulls used for artificial insemination (AI) on semen motility and kinematic variables measured with CASA systems. Eight animals of Holstein and Jersey breeds were used, and nine frozen-thawed semen doses per animal were analyzed for each breed. Three temperatures (35, 37, and 40 °C) and three thawing times (35, 40, and 45 s) were evaluated using a factorial design. Motility and kinematic patterns were analyzed using CASA-mot (Computer-Assisted Semen Analysis of motility) technology at different post-thawing times (0.5, 1, and 2 h). Sperm motility in Jersey bulls was higher (p < 0.05) than in Holstein ones (64.52 ± 1.45% and 53.10 ± 1.40%, respectively). The same effect was seen with progressive motility among the two breeds (Jersey: 45.29 ± 1.00%; Holstein: 36.30 ± 0.98%, p < 0.05). The Jersey breed presented higher values (p < 0.05) of curvilinear velocity (VCL), rectilinear velocity (VSL), average velocity (VAP), linearity on forward progression (LIN), and wobble (WOB). The Holstein breed showed a lower mean value (p < 0.05) of the beat-cross frequency (BCF) compared to the Jersey breed, thus suggesting an effect on VCL and VAP. During the post-thaw period, a gradual increase in VCL was observed at 2 h. VSL and VAP showed a decrease (p < 0.05) as the post-thaw period was prolonged. The study showed differences in sperm quality between Holstein and Jersey breeds, influenced by cryopreservation, thawing, and post-thawing incubation. Thawing at 37 °C for 30 s was considered optimal in relation to sperm motility. In addition, a decrease in sperm quality was observed as post-thawing time increased.

High-resolution versus conventional manometry for the diagnosis of small bowel motor dysfunction.

The diagnosis of small bowel motility disorders is performed by manometric evaluation of the contractile patterns of the small intestine. Conventional intestinal manometry systems include few pressure sensors at relatively long intervals. We have recently shown that high-resolution jejunal manometry, with multiple closely spaced recording sites, allows the analysis of propagation patterns of intestinal motility in healthy subjects that cannot be detected with conventional manometry. The objective of this pilot study was to explore the feasibility and diagnostic value of high-resolution intestinal manometry in patients with suspected small bowel dysmotility. Prospective pilot study evaluating intestinal motility patterns in 16 consecutive patients (16-61 years; 11 women) with severe, chronic digestive symptoms referred for the evaluation of intestinal motility and in 18 healthy controls (21-38 years; 8 women). A 36-channel high-resolution manometry catheter was orally placed under radiological guidance in the jejunum. Intestinal motility was continuously recorded for 3 h fasting and 2 h after a 450 kcal meal. The manometric recordings were analyzed in two formats: (a) with the high-resolution data from 34 channels and (b) showing only the recordings from 5 channels separated by 7 cm intervals, mimicking a conventional manometry recording. In the analysis mimicking conventional manometry, abnormal motility criteria were detected in six patients and in no healthy subject [bursts (n = 3), postprandial minute rhythm (n = 1) and myopathic pattern (n = 2)]. These classical dysmotility criteria were also detected by high-resolution manometry. High-resolution analysis detected one or more abnormal findings in seven additional patients that were not observed in any healthy subject, specifically: (a) abnormal propagation of Phase III (n = 3); (b) reduced propagated activity during Fasting Phase II (n = 4); (c) increased propagated activity during Fasting Phase II and postprandial phase (n = 1). This pilot study suggests that high-resolution intestinal manometry may improve the sensitivity of conventional manometry in the detection of intestinal motor dysfunction.

Quantitative Analysis of Small Intestinal Motility in 3D Cine-MRI Using Centerline-Aware Motion Estimation.

Currently available tools for noninvasive motility quantification of the small intestine are limited to dynamic 2D MRI scans, which are limited in their ability to differentiate between types of intestinal motility. To develop a method for quantification and characterization of small intestinal motility in 3D, capable of differentiating motile, non-motile and peristaltic motion patterns. Prospective. Fourteen healthy volunteers (127 small intestinal segments) and 10 patients with Crohn's disease (87 small intestinal segments). 3.0 T, 3D balanced fast field echo sequence, 1 volume per second. Using deformable image registration between subsequent volumes, the local velocity within the intestinal lumen was quantified. Average velocity and average absolute velocity along intestinal segments were used with linear classifiers to differentiate motile from non-motile intestines, as well as erratic motility from peristalsis. The mean absolute velocity of small intestinal content was compared between healthy volunteers and Crohn's disease patients, and the discriminative power of the proposed motility metrics for detecting motility and peristalsis was determined. The consensus of two observers was used as referenced standard. Student's t-test to assess differences between groups; area under the receiver operating characteristic curve (AUC) to assess discriminative ability. P < 0.001 was considered significant. A significant difference in the absolute velocity of intestinal content between Crohn's patients and healthy volunteers was observed (median [IQR] 1.06 [0.61, 1.56] mm/s vs. 1.84 [1.37, 2.43] mm/s), which was consistent with manual reference annotations of motile activity. The proposed method had a strong discriminative performance for detecting non-motile intestines (AUC 0.97) and discernible peristalsis (AUC 0.81). Analysis of 3D cine-MRI using centerline-aware motion estimation has the potential to allow noninvasive characterization of small intestinal motility and peristaltic motion in 3D. 3 TECHNICAL EFFICACY: Stage 2.

EndoFLIP Use in De Novo and Revisional Foregut Surgery

AbstractEndoFLIP technology, utilizing impedance planimetry, has revolutionized the assessment of gastrointestinal sphincters by providing real-time measurements of cross-sectional area and pressure to calculate distensibility. This review explores its application in de novo and revisional foregut surgeries. Preoperatively, EndoFLIP has demonstrated efficacy in evaluating gastroesophageal reflux disease, hiatal hernia, and esophageal motility disorders, including achalasia, by distinguishing motility patterns and identifying sphincter incompetence. In gastroparesis, EndoFLIP's measurement of pyloric distensibility correlates with gastric emptying and symptom severity, guiding therapeutic decisions for pyloric interventions. Intraoperatively, EndoFLIP optimizes surgical outcomes in antireflux procedures, such as fundoplication and hiatal hernia repairs, by balancing effective reflux control with minimizing postoperative complications like dysphagia and gas bloat. For esophageal myotomy, including Heller myotomy and per oral endoscopic myotomy, EndoFLIP ensures adequate sphincter relaxation, reducing reflux risks. Additionally, during endoscopic pyloromyotomy for gastroparesis, EndoFLIP predicts clinical success by assessing postprocedural distensibility. While promising, further research is essential to establish standardized intraoperative protocols and ideal measurement targets, enhancing the reproducibility and accuracy of EndoFLIP applications. Overall, EndoFLIP offers a significant advancement in foregut surgery, improving diagnostic precision and therapeutic outcomes.

Decreases in mucosally-evoked tachykinin signaling pathways can explain age-related reductions in murine colonic motility patterns.

Increasing age increases the incidence of chronic constipation and fecal impaction. The contribution of the natural aging process to this phenotype is unclear. This study explored the effects of age on key motility patterns in the murine colon and determined the contribution that altered neurokinin 2 (NK2) -mediated signaling made to the aging phenotype. Mucosal reflexes, colonic migrating motor complexes (CMMCs) and colonic motility assays were explored in isolated exvivo colons from 3, 12-14, 18- and 24-months old mice and the NK2-mediated response determined. Electrical field stimulation (EFS) or exogenous drug application were used to explore the role of the mucosa in colonic segments. Aging reduced the force of contraction of the distal colon mucosal reflex, the frequency and force of contraction of CMMCs and the NK2-mediated component of both motility patterns. Ondansetron, a 5-HT3 receptor antagonist, blocked a component of both motility patterns in full thickness but not in mucosa-free segments of the distal colon. 5, hydroxytryptamine (5-HT) and EFS-evoked NK2-dependent contractions were reduced with increasing age. Smooth muscle sensitivity to 5-HT or neurokinin A (NKA) was not altered with age. In isolated colon motility assays application of NKA decreased transit time in 24-months colon and the NK2 antagonist GR159897 increased transit times in both 3- and 24-months old colons. Aging impairs key motility patterns in the murine colon. These changes involve a decrease in mucosally-evoked NK2-mediated signaling. Targeting NK2-mediated signaling may provide a novel approach to treating age-related motility disorders in the lower bowel.

Relationship between season and spermatozoa traits of captive-reared agoutis from Brazilian semiarid.

For the development of efficient management and conservation strategies for wild rodent species, understanding the aspects related to their reproduction, including the interaction of this physiological function with the environment, is essential. This study aimed to evaluate the impacts of weather changes derived from a semiarid region's dry and rainy seasons on the epididymal sperm characteristics of red-rumped agouti (Dasyprocta leporina), a histricognath rodent, still little studied, which inhabits the Brazilian Caatinga. The sperm from the epididymal cauda of 14 agoutis were collected, seven individuals per season (dry and rainy). Samples were evaluated for kinetic parameters, membrane structural and functional integrity, mitochondrial activity, morphology, and morphometry. The environmental variables were measured: maximum air temperature, relative humidity, wind speed, solar radiation, and the total rainfall for dry and rainy seasons were, respectively, 36.2 and 34.1°C, 66.8 and 80.1%, 4.0 and 1.9m/s, 527.3 and 441.8 W/m2, and 0.2 and 517.7mm. There were strong correlations between some sperm parameters and environmental variables, mainly those related to the acquisition of sperm mobility. Sperm concentration and the number of sperm collected were higher in the dry (1028.7 sperm/mL × 10⁶ and 1361.2 × 106 sperm) than in the rainy season (758.9 sperm × 10⁶/mL and 714.6 sperm × 106). During the rainy season, there were fewer sperm defects, higher sperm metrics, and higher membrane structural integrity with mitochondrial activity. Regarding motility patterns, the increases during the rainy season stand out in total and progressive motility, VAP, VSL, VCL, and subpopulations of rapid sperm. In summary, our results suggest that the adverse climatic conditions of the dry season in the semiarid region, mainly high solar radiation and temperature, considerably impair the epididymal sperm quality of red-rumped agoutis. On the contrary, the largest amount of sperm was obtained during this season, probably due to compensatory and adaptive mechanisms of the species to enable its reproduction throughout the year.

Spontaneous enteric nervous system activity generates contractile patterns prior to maturation of gastrointestinal motility.

Spontaneous neuronal network activity is essential to the functional maturation of central and peripheral circuits, yet whether this is a feature of enteric nervous system development has yet to be established. Although enteric neurons are known exhibit electrophysiological properties early in embryonic development, no connection has been drawn between this neuronal activity and the development of gastrointestinal (GI) motility patterns. We use exvivo GI motility assays with newly developed unbiased computational analyses to identify GI motility patterns across mouse embryonic development. We find a previously unknown pattern of neurogenic contractions termed "clustered ripples" that arises spontaneously at embryonic day 16.5, an age earlier than any identified mature GI motility patterns. We further show that these contractions are driven by nicotinic cholinergic signaling. Clustered ripples are neurogenic contractile activity that arise from spontaneous ENS activity and precede all known forms of neurogenic GI motility. This earliest motility pattern requires nicotinic cholinergic signaling, which may inform pharmacology for enhancing GI motility in preterm infants.

Aberrant migration features in primary skin fibroblasts of Huntington's disease patients hold potential for unraveling disease progression using an image based machine learning tool

Huntington's disease (HD) is a complex neurodegenerative disorder with considerable heterogeneity in clinical manifestations. While CAG repeat length is a known predictor of disease severity, this heterogeneity suggests the involvement of additional genetic and environmental factors. Previously we revealed that HD primary fibroblasts exhibit unique features, including distinct nuclear morphology and perturbed actin cap, resembling characteristics seen in Hutchinson-Gilford Progeria Syndrome (HGPS). This study establishes a link between actin cap deficiency and cell motility in HD, which correlates with the HD patient disease severity. Here, we examined single-cell motility imaging features in HD primary fibroblasts to explore in depth the relationship between cell migration patterns and their respective HD patients' clinical severity status (premanifest, mild and severe). The single-cell analysis revealed a decline in overall cell motility in correlation with HD severity, being most prominent in severe HD subgroup and HGPS. Moreover, we identified seven distinct spatial clusters of cell migration in all groups, which their proportion varies within each group becoming a significant HD severity classifier between HD subgroups. Next, we investigated the relationship between Lamin B1 expression, serving as nuclear envelope morphology marker, and cell motility finding that changes in Lamin B1 levels are associated with specific motility patterns within HD subgroups. Based on these data we present an accurate machine learning classifier offering comprehensive exploration of cellular migration patterns and disease severity markers for future accurate drug evaluation opening new opportunities for personalized treatment approaches in this challenging disorder.

Biomimetic Synchronization in Biciliated Robots.

Direct mechanical coupling is known to be critical for establishing synchronization among cilia. However, the actual role of the connections is still elusive-partly because controlled experiments in living samples are challenging. Here, we employ an artificial ciliary system to address this issue. Two cilia are formed by chains of self-propelling robots and anchored to a shared base so that they are purely mechanically coupled. The system mimics biological ciliary beating but allows fine control over the beating dynamics. With different schemes of mechanical coupling, artificial cilia exhibit rich motility patterns. Particularly, their synchronous beating display two distinct modes-analogous to those observed in C. reinhardtii, the biciliated model organism for studying synchronization. Close examination suggests that the system evolves towards the most dissipative mode. Using this guideline in both simulations and experiments, we are able to direct the system into a desired state by altering the modes' respective dissipation. Our results have significant implications in understanding the synchronization of cilia.

A geometrical theory of gliding motility based on cell shape and surface flow

Gliding motility proceeds with little changes in cell shape and often results from actively driven surface flows of adhesins binding to the extracellular environment. It allows for fast movement over surfaces or through tissue, especially for the eukaryotic parasites from the phylum apicomplexa, which includes the causative agents of the widespread diseases malaria and toxoplasmosis. We have developed a fully three-dimensional active particle theory which connects the self-organized, actively driven surface flow over a fixed cell shape to the resulting global motility patterns. Our analytical solutions and numerical simulations show that straight motion without rotation is unstable for simple shapes and that straight cell shapes tend to lead to pure rotations. This suggests that the curved shapes of Plasmodium sporozoites and Toxoplasma tachyzoites are evolutionary adaptations to avoid rotations without translation. Gliding motility is also used by certain myxo- or flavobacteria, which predominantly move on flat external surfaces and with higher control of cell surface flow through internal tracks. We extend our theory for these cases. We again find a competition between rotation and translation and predict the effect of internal track geometry on overall forward speed. While specific mechanisms might vary across species, in general, our geometrical theory predicts and explains the rotational, circular, and helical trajectories which are commonly observed for microgliders. Our theory could also be used to design synthetic microgliders.

Functional lumen imaging probe use in a high-volume practice: Practical and technical implications.

The functional lumen imaging probe (FLIP) is a Food and Drug Administration approved tool to aid the diagnosis and management of esophageal disorders. However, widespread adoption of FLIP remains limited and its utility in high-volume practices remains unclear. To analyze large sample data on clinical use of FLIP and provide insight on several technical aspects when performing FLIP. We conducted a retrospective comparative and descriptive analysis of FLIP procedures performed by a single provider at an academic medical center. There was a total of 398 FLIP procedures identified. Patient medical records were reviewed and data regarding demographics and procedural details were collected. Statistical tests, including chi-squared, t-test, and multivariable logistic and linear regression, were performed. There was an increase in FLIP cases with each successive time period of 13 months (n = 68, 146, 184, respectively) with notable rises specifically for indications of dysphagia and gastroesophageal reflux disease. There was a shift toward use of the longer FLIP balloon catheter for diagnostic purposes (overall 70.4% vs 29.6%, P < 0.01). Many cases (42.8%) were performed in conjunction with other diagnostics/interventions, such as dilation and wireless pH probe placement. Procedures were nearly equally performed with anesthesia vs moderate sedation (51.4% anesthesia), with no major complications. Patients who had anesthesia were less likely to have recurrent antegrade contractions [odds ratio (OR) = 0.4, 95%CI: 0.3-0.8] and were also more likely to have absent contractility (OR = 2.4, 95%CI: 1.3-4.4). FLIP cases have increased in our practice with expanding indications for its use. Given limited normative data, providers should be aware of several potential technical issues, including the possible impact of sedation choice when assessing esophageal motility patterns.

Lead and calcium crosstalk tempted acrosome damage and hyperpolarization of spermatozoa: signaling and ultra-structural evidences

BackgroundExposure of humans and animals to heavy metals is increasing day-by-day; thus, lead even today remains of significant public health concern. According to CDC, blood lead reference value (BLRV) ranges from 3.5 µg/dl to 5 μg/dl in adults. Recently, almost 2.6% decline in male fertility per year has been reported but the cause is not well established. Lead (Pb2+) affects the size of testis, semen quality, and secretory functions of prostate. But the molecular mechanism(s) of lead toxicity in sperm cells is not clear. Thus, present study was undertaken to evaluate the adverse effects of lead acetate at environmentally relevant exposure levels (0.5, 5, 10 and 20 ppm) on functional and molecular dynamics of spermatozoa of bucks following in vitro exposure for 15 min and 3 h.ResultsLead significantly decreased motility, viable count, and motion kinematic patterns of spermatozoa like curvilinear velocity, straight-line velocity, average path velocity, beat cross frequency and maximum amplitude of head lateral displacement even at 5 ppm concentration. Pb2+ modulated intracellular cAMP and Ca2+ levels in sperm cells through L-type calcium channels and induced spontaneous or premature acrosome reaction (AR) by increasing tyrosine phosphorylation of sperm proteins and downregulated mitochondrial transmembrane potential. Lead significantly increased DNA damage and apoptosis as well. Electron microscopy studies revealed Pb2+ -induced deleterious effects on plasma membrane of head and acrosome including collapsed cristae in mitochondria.ConclusionsPb2+ not only mimics Ca2+ but also affects cellular targets involved in generation of cAMP, mitochondrial transmembrane potential, and ionic exchange. Lead seems to interact with Ca2+ channels because of charge similarity and probably enters the sperm cell through these channels and results in hyperpolarization. Our findings also indicate lead-induced TP and intracellular Ca2+ release in spermatozoa which in turn may be responsible for premature acrosome exocytosis which is essential feature of capacitation for fertilization. Thus, lead seems to reduce the fertilizing capacity of spermatozoa even at 0.5 ppm concentrations.Graphical

Plasmodium sporozoite shows distinct motility patterns in responses to three-dimensional environments

During malaria infection, Plasmodium sporozoites, the fast-moving stage of the parasite, are injected by a mosquito into the skin of the mammalian host. In the skin, sporozoites need to migrate through the dermal tissue to enter the blood vessel. Sporozoite motility is critical for infection but not well understood. Here, we used collagen hydrogels with tunable fiber structures, as an invitro model for the skin. After injecting sporozoites into the hydrogel, we analyzed their motility in three-dimension (3D). We found that sporozoites demonstrated chiral motility, in that they mostly follow right-handed helical trajectories. In high-concentration collagen gel, sporozoites have lower instantaneous speed, but exhibit straighter tracks compared to low-concentration collagen gel, which leads to longer net displacement and faster dissemination. Taken together, our study indicates an inner mechanism for sporozoites to adapt to the environment, which could help with their successful exit from the skin tissue.

Compressed intracellular motility via non-uniform temporal sampling in dynamic optical coherence tomography.

Optical coherence tomography has great utility for capturing dynamic processes, but such applications are particularly data-intensive. Samples such as biological tissues exhibit temporal features at varying time scales, which makes data reduction challenging. We propose a method for capturing short- and long-term correlations of a sample in a compressed way using non-uniform temporal sampling to reduce scan time and memory overhead. The proposed method separates the relative contributions of white noise, fluctuating features, and stationary features. The method is demonstrated on mammary epithelial cell spheroids in three-dimensional culture for capturing intracellular motility without loss of signal integrity. Results show that the spatial patterns of motility are preserved and that hypothesis tests of spheroids treated with blebbistatin, a motor protein inhibitor, are unchanged with up to eightfold compression. The ability to measure short- and long-term correlations compressively will enable new applications in (3+1)D imaging and high-throughput screening.