Motile Phase Research Articles

Transport of topological defects in a biphasic mixture of active and passive nematic fluids

Collectively moving cellular systems often contain a proportion of dead cells or non-motile genotypes. When mixed, nematically aligning motile and non-motile agents are known to segregate spontaneously. However, the role that topological defects and active stresses play in shaping the distribution of the two phases remains unresolved. In this study, we investigate the behaviour of a two-dimensional binary mixture of active and passive nematic fluids to understand how topological defects are transported between the two phases and, ultimately, how this leads to the segregation of topological charges. When the activity of the motile phase is large, and the tension at the interface of motile and non-motile phases is weak, we find that the active phase tends to accumulate +1/2 defects and expel −1/2 defects so that the motile phase develops a net positive charge. Conversely, when the activity of the motile phase is comparatively small and interfacial tension is strong, the opposite occurs so that the active phase develops a net negative charge. We then use these simulations to develop a physical intuition of the underlying processes that drive the charge segregation. Lastly, we quantify the sensitivity of this process on the other model parameters, by exploring the effect that anchoring strength, orientational elasticity, friction, and volume fraction of the motile phase have on topological charge segregation. As +1/2 and −1/2 defects have very different effects on interface morphology and fluid transport, this study offers new insights into the spontaneous pattern formation that occurs when motile and non-motile cells interact.

Lipidomic and Proteomic Insights from Extracellular Vesicles in Postmortem Dorsolateral Prefrontal Cortex Reveal Substance Use Disorder-Induced Brain Changes.

Substance use disorder (SUD) significantly increases the risk of neurotoxicity, inflammation, oxidative stress, and impaired neuroplasticity. The activation of inflammatory pathways by substances may lead to glial activation and chronic neuroinflammation, potentially mediated by the release of extracellular particles (EPs), such as extracellular condensates (ECs) and extracellular vesicles (EVs). These particles, which reflect the physiological, pathophysiological, and metabolic states of their cells of origin, might carry molecular signatures indicative of SUD. In particular, our study investigated neuroinflammatory signatures in SUD by isolating EVs from the dorsolateral prefrontal cortex (dlPFC) Brodmann's area 9 (BA9) in postmortem subjects. We isolated BA9-derived EVs from postmortem brain tissues of eight individuals (controls: n=4, SUD: n=4). The EVs were analyzed for physical properties (concentration, size, zeta potential, morphology) and subjected to integrative multi-omics analysis to profile the lipidomic and proteomic characteristics. We assessed the interactions and bioactivity of EVs by evaluating their uptake by glial cells. We further assessed the effects of EVs on complement mRNA expression in glial cells as well as their effects on microglial migration. No significant differences in EV concentration, size, zeta potential, or surface markers were observed between SUD and control groups. However, lipidomic analysis revealed significant enrichment of glycerophosphoinositol bisphosphate (PIP2) in SUD EVs. Proteomic analysis indicates downregulation of SERPINB12, ACYP2, CAMK1D, DSC1, and FLNB, and upregulation of C4A, C3, and ALB in SUD EVs. Gene ontology and protein-protein interactome analyses highlight functions such as cell motility, focal adhesion, and acute phase response signaling that is associated with the identified proteins. Both control and SUD EVs increased C3 and C4 mRNA expression in microglia, but only SUD EVs upregulated these genes in astrocytes. SUD EVs also significantly enhanced microglial migration in a wound healing assay.This study successfully isolated EVs from postmortem brains and used a multi-omics approach to identify EV-associated lipids and proteins in SUD. Elevated C3 and C4 in SUD EVs and the distinct effects of EVs on glial cells suggest a crucial role in acute phase response signaling and neuroinflammation.

Involvement of ArlI, ArlJ, and CirA in archaeal type IV pilin-mediated motility regulation.

Many prokaryotes use swimming motility to move toward favorable conditions and escape adverse surroundings. Regulatory mechanisms governing bacterial flagella-driven motility are well-established; however, little is yet known about the regulation underlying swimming motility propelled by the archaeal cell surface structure, the archaella. Previous research showed that the deletion of the adhesion pilins (PilA1-6), subunits of the type IV pili cell surface structure, renders the model archaeon Haloferax volcanii non-motile. In this study, we used ethyl methanesulfonate mutagenesis and a motility assay to identify motile suppressors of the ∆pilA[1-6] strain. Of the eight suppressors identified, six contain missense mutations in archaella biosynthesis genes, arlI and arlJ. In trans expression of arlI and arlJ mutant constructs in the respective multi-deletion strains ∆pilA[1-6]∆arlI and ∆pilA[1-6]∆arlJ confirmed their role in suppressing the ∆pilA[1-6] motility defect. Additionally, three suppressors harbor co-occurring disruptive missense and nonsense mutations in cirA, a gene encoding a proposed regulatory protein. A deletion of cirA resulted in hypermotility, while cirA expression in trans in wild-type cells led to decreased motility. Moreover, quantitative real-time PCR analysis revealed that in wild-type cells, higher expression levels of arlI, arlJ, and the archaellin gene arlA1 were observed in motile early-log phase rod-shaped cells compared to non-motile mid-log phase disk-shaped cells. Conversely, ∆cirA cells, which form rods during both early- and mid-log phases, exhibited similar expression levels of arl genes in both growth phases. Our findings contribute to a deeper understanding of the mechanisms governing archaeal motility, highlighting the involvement of ArlI, ArlJ, and CirA in pilin-mediated motility regulation.IMPORTANCEArchaea are close relatives of eukaryotes and play crucial ecological roles. Certain behaviors, such as swimming motility, are thought to be important for archaeal environmental adaptation. Archaella, the archaeal motility appendages, are evolutionarily distinct from bacterial flagella, and the regulatory mechanisms driving archaeal motility are largely unknown. Previous research has linked the loss of type IV pili subunits to archaeal motility suppression. This study reveals three Haloferax volcanii proteins involved in pilin-mediated motility regulation, offering a deeper understanding of motility regulation in this understudied domain while also paving the way for uncovering novel mechanisms that govern archaeal motility. Understanding archaeal cellular processes will help elucidate the ecological roles of archaea as well as the evolution of these processes across domains.

Microscopic and molecular genetic analyses of morphological development of the actinomycete Actinoplanes missouriensis.

The survival strategy of members of the bacterial genus Actinoplanes is fascinating from morphological and evolutionary perspectives. A brief motile phase is incorporated in the filamentous and resting stages of the life cycle of Actinoplanes missouriensis. Spores either lie dormant or swim under different external conditions. This review presents microscopic observations and molecular genetic analyses of A. missouriensis morphological development. Selected examples of the characterization of developmental genes and their products are also introduced.

A computational model for early cell spreading, migration, and competing taxis

Cell motility represents one of the most fundamental functions in life such as organ development or tissue regeneration and diseases such as cancer. Here, we derived a computational model of cell motility that incorporates the most important mechanisms towards cell motility: cell protrusion, polarization, and retrograde flow. We first validate our model to explain the main phases of cell motility, i.e. symmetric cell spreading, cell polarization, and two important types of cell migration, confined and amoeboid cell migration. Then, we use our model to investigate the effect of chemical and mechanical signals in cell migration, that is chemotaxis and durotaxis. More importantly, we analyze the competition between durotaxis and chemotaxis. We show that chemotaxis rules over durotaxis in most situations although durotaxis can diminish chemotaxis. Moreover, we show that inhibiting the effect of GTPases in actin polymerization at the cell front may allow durotaxis to take control over chemotaxis in soft substrates. Understanding how the main forces in cell motility cooperate, and how a precise manipulation of external cues may control directed cell migration is not only key for a fundamental comprehension of cell biology but also plays a key role in the future of tissue and biomedical engineering. To this end, we provide a freely-available platform to predict all phases and modes of cell motility analyzed in this work.

High-Resolution Tracking of Dynein-Dynactin-BicD2 Complexes.

The adapter dynactin and the activator BicD2 associate with dynein to form the highly motile dynein-dynactin-BicD2 (DDB) complex. In single-molecule assays, DDB displays processive runs, diffusive episodes, and transient pauses. The switching rates and durations of the different phases can be determined by tracking gold nanoparticle-labeled DDB complexes with interferometric scattering (iSCAT) microscopy and using an algorithm to separate out different motility phases. Here we describe methods for purifying DDB complexes from brain lysate, labeling with gold nanoparticles, imaging by iSCAT, and analyzing the resulting trajectories.

Cell motility as an energy minimization process.

The dynamics of active matter driven by interacting molecular motors has a nonpotential structure at the local scale. However, we show that there exists a quasipotential effectively describing the collective self-organization of the motors propelling a cell at a continuum active gel level. Such a model allows us to understand cell motility as an active phase transition problem between the static and motile steady-state configurations that minimize the quasipotential. In particular, both configurations can coexist in a metastable fashion and a small stochastic disorder in the gel is sufficient to trigger an intermittent cell dynamics where either static or motile phases are more probable, depending on which state is the global minimum of the quasipotential.

Impact of spatial pattern of obstacles on first passage of an active particle

Recent studies suggest that structural features of environments have a significant impact on the motility phases of active matter biological systems. The active particles consume energy to convert it into directed motion. Our study is particularly motivated by the physics behind the formation of large chromosomal loops mediated by Loop Extrusion factor proteins like cohesion which walk diffusively on DNA where nucleosomes act as obstacles to diffusion reducing the permeability. We have designed an experimental system in macroscale which mimics such a behavior and we explore the nature of diffusion in such an active system.

P–036 Investigation of the 2100 MHz electromagnetic field effects on sperm CatSper calcium channel

Abstract Study question Does electromagnetic field (EMF) effect sperm motility through CatSper calcium channels in rat? Summary answer 2100 MHz EMF may reduce sperm motility by acting on CatSper calcium channels. What is known already EMF exposure has become a serious concern in infertility patients. The effects of EMF through by using mobile phone and laptop have been explored previously, mostly focusing on sperm motility and DNA fragmentation. EMF activates the voltage gated calcium channels and increases calcium concentration. As a result of the EMA exposure, the sperm motility may increase. However, if this happens while sperms are in non-progressive motile phase in the epididymis, it may result with the depletion of limited energy stores. Sperms may become immotile and they can’t move forward in the progressive motile phase in the female reproductive system. Study design, size, duration This basic research study was an in vivo experimental approach involving the use of 50 male rats. Wistar-Albino rats (n = 10) weighing ∼320 –350g were included in each groups. The duration of EMF exposure was 1 hour per day for 28 days. Amlodipine (1 mg/kg, 28 days) was used as a calcium channel blocker. The experiment was held between July to December in 2020. 20 female rats were recruited for mating test. Participants/materials, setting, methods 50 rats were divided into five groups. Group 1; Pure control. Group 2; Sham. Group 3; EMF exposure, Group 4: EMF+Amlodipine, Group 5: Amlodipine positive control. After four weeks of exposure, rats were sacrificed and sperm were collected from cauda epididymis. Sperm motility parameters were analyzed. Intracellular calcium levels were determined with two different method, fluorescence spectrophotometer and laser scanning confocal microscope. Before sacrifice, rats were mated with female rats to evaluate mating ratios. Main results and the role of chance The mating score and live birth rates did not vary significantly among the groups (p > 0.05). The sperm motility (A+B, 47.62±16.92 versus 34.19±14.62) and intracellular calcium levels (2.46±0.20 versus 1.85±0.18) were significantly decreased in the EMF group (p < 0.05). The results of fluorescence spectrophotometer and laser scanning confocal microscopy with fluorescent attachment were consistent with each other. There were no significant differences found among the other groups in terms of investigated parameters. Statistical analysis was performed with Kruskal-Wallis test followed by the Dunn-Bonferroni’s test. Limitations, reasons for caution The Catsper 1, 2, 3, 4 gene expression levels are still under analyses. These gene expression levels will be helpful to understand possible changes of the sperm motility. The determination of other motility related gene expressions may strength the results. Wider implications of the findings: EMF exposure may have a significant effect on sperm motility parameters. Mobile phones carried very close to the reproductive organs may adversely affect the motility of sperm cells due to its emitted radiation levels Trial registration number Not applicable

To hunt or to rest: prey depletion induces a novel starvation survival strategy in bacterial predators.

The small size of bacterial cells necessitates rapid adaption to sudden environmental changes. In Bdellovibrio bacteriovorus, an obligate predator of bacteria common in oligotrophic environments, the non-replicative, highly motile attack phase (AP) cell must invade a prey to ensure replication. AP cells swim fast and respire at high rates, rapidly consuming their own contents. How the predator survives in the absence of prey is unknown. We show that starvation for prey significantly alters swimming patterns and causes exponential decay in prey-searching cells over hours, until population-wide swim-arrest. Swim-arrest is accompanied by changes in energy metabolism, enabling rapid swim-reactivation upon introduction of prey or nutrients, and a sweeping change in gene expression and gene regulation that largely differs from those of the paradigmatic stationary phase. Swim-arrest is costly as it imposes a fitness penalty in the form of delayed growth. We track the control of the swim arrest-reactivation process to cyclic-di-GMP (CdG) effectors, including two motility brakes. CRISPRi transcriptional inactivation, and in situ localization of the brakes to the cell pole, demonstrated their essential role for effective survival under prey-induced starvation. Thus, obligate predators evolved a unique CdG-controlled survival strategy, enabling them to sustain their uncommon lifestyle under fluctuating prey supply.

Crustose coralline algae that promote coral larval settlement harbor distinct surface bacterial communities

Most benthic invertebrates, including ecosystem engineers such as corals, sponges and bivalves, have a motile planktonic larval phase and rely on specific chemical cues to identify a suitable substrate to settle. Crustose coralline algae (CCA) can induce settlement and metamorphosis responses in many invertebrates including corals. We tested the respective coral settlement capacity of multiple CCA species in a choice experiment and investigated the composition of their microbiomes. Our findings revealed that coral larval settlement was drastically influenced by CCA genera and also suggest that bacterial communities on the CCA surface can potentially serve as a driver of coral larval settlement. The composition of the bacterial communities on the surface of the least attractive CCA genus, Neogoniolithon fosliei, was markedly different from the other genera, Porolithon gardineri and Titanoderma prototypum and was significantly enriched in Vibrio and Flammeovirgaceae. The activity of CCA-associated bacterial communities may contribute to some of the variability observed in settlement responses between CCA species. Specific bacterial ASVs assigned to the Neptuniibacter, Methylotrophic Group 3 and Cellvibrionaceae were positively correlated with coral settlement. Conversely, ASVs assigned as Vibrio and Flammeovirga were negatively correlated with coral settlement. This study identifies putative bacterial taxa involved in coral settlement, which is an essential step to understand the chemical cues involved in this process and to predict the ability of corals to recolonize damaged reefs following disturbances.

Neurobiology: Swimming at the Intersection of Light and Gravity.

Many animals use gravity as a spatial reference to help navigate their surroundings, but how they do so is not well understood. A new study reveals that a representative of our closest invertebrate relatives, the tunicate Ciona, processes light and gravity cues through a simple neural circuit to decide when and how to swim.

Activity within specific enteric neurochemical subtypes is correlated with distinct patterns of gastrointestinal motility in the murine colon.

The enteric nervous system in the large intestine generates two important patterns relating to motility: 1) propagating rhythmic peristaltic smooth muscle contractions referred to as colonic migrating motor complexes (CMMCs) and 2) tonic inhibition, during which colonic smooth muscle contractions are suppressed. The precise neurobiological substrates underlying each of these patterns are unclear. Using transgenic animals expressing the genetically encoded calcium indicator GCaMP3 to monitor activity or the optogenetic actuator channelrhodopsin (ChR2) to drive activity in defined enteric neuronal subpopulations, we provide evidence that cholinergic and nitrergic neurons play significant roles in mediating CMMCs and tonic inhibition, respectively. Nitrergic neurons [neuronal nitric oxide synthase (nNOS)-positive neurons] expressing GCaMP3 exhibited higher levels of activity during periods of tonic inhibition than during CMMCs. Consistent with these findings, optogenetic activation of ChR2 in nitrergic neurons depressed ongoing CMMCs. Conversely, cholinergic neurons [choline acetyltransferase (ChAT)-positive neurons] expressing GCaMP3 markedly increased their activity during the CMMC. Treatment with the NO synthesis inhibitor Nω-nitro-l-arginine also augmented the activity of ChAT-GCaMP3 neurons, suggesting that the reciprocal patterns of activity exhibited by nitrergic and cholinergic enteric neurons during distinct phases of colonic motility may be related.NEW & NOTEWORTHY Correlating the activity of neuronal populations in the myenteric plexus to distinct periods of gastrointestinal motility is complicated by the difficulty of measuring the activity of specific neuronal subtypes. Here, using mice expressing genetically encoded calcium indicators or the optical actuator channelrhodopsin-2, we provide compelling evidence that cholinergic and nitrergic neurons play important roles in mediating coordinated propagating peristaltic contractions or tonic inhibition, respectively, in the murine colon.

Learning the space-time phase diagram of bacterial swarm expansion

Coordinated dynamics of individual components in active matter are an essential aspect of life on all scales. Establishing a comprehensive, causal connection between intracellular, intercellular, and macroscopic behaviors has remained a major challenge due to limitations in data acquisition and analysis techniques suitable for multiscale dynamics. Here, we combine a high-throughput adaptive microscopy approach with machine learning, to identify key biological and physical mechanisms that determine distinct microscopic and macroscopic collective behavior phases which develop as Bacillus subtilis swarms expand over five orders of magnitude in space. Our experiments, continuum modeling, and particle-based simulations reveal that macroscopic swarm expansion is primarily driven by cellular growth kinetics, whereas the microscopic swarming motility phases are dominated by physical cell-cell interactions. These results provide a unified understanding of bacterial multiscale behavioral complexity in swarms.

Chemotactic Motility and Growth of Pseudomonas fluorescens Towards Glucose Concentration

Pseudomonas fluorescens is plant growth promoting rhizobacteria (PGPR) often inoculated on plants as natural biocontrol agent capable of protecting the plants from soil-borne pathogens. Chemotactic motility allows populations of P. fluorescens to rapidly search for nutrients and is an important factor determining their competitive success to colonize plant root. Therefore, we investigated various glucose concentrations from 0% to 1% (w/v) to enhance chemotactic motility and growth of this rhizobia. Chemotactic motility was evaluated using swim plate assay and bacterial growth was measured using UV-Vis Spectrophotometer in LB and M9 medium. Glucose with low concentration (0.05%) showed to have optimum response in P. fluorescens chemotactic motility with colony diameter 38.3 mm in LB medium and 12.8 mm in M9 medium. Highest growth of P. fluorescens was seen in control condition of LB medium reaching a peak at 0.0246 OD600 (~±1,44x107 CFU ml-1 ) while growth in M9 medium supplemented with 1% glucose was just slightly lower with 0.0227 OD600 (~±1,32x107 CFU ml-1). Glucose in high concentration showed to repress chemotactic motility and first growth phase of P. fluorescens in LB medium due to catabolite repression.

Increased Calcium Influx through L-type Calcium Channels in Human and Mouse Neural Progenitors Lacking Fragile X Mental Retardation Protein.

SummaryThe absence of FMR1 protein (FMRP) causes fragile X syndrome (FXS) and disturbed FMRP function is implicated in several forms of human psychopathology. We show that intracellular calcium responses to depolarization are augmented in neural progenitors derived from human induced pluripotent stem cells and mouse brain with FXS. Increased calcium influx via nifedipine-sensitive voltage-gated calcium (Cav) channels contributes to the exaggerated responses to depolarization and type 1 metabotropic glutamate receptor activation. The ratio of L-type/T-type Cav channel expression is increased in FXS progenitors and correlates with enhanced progenitor differentiation to glutamate-responsive cells. Genetic reduction of brain-derived neurotrophic factor in FXS mouse progenitors diminishes the expression of Cav channels and activity-dependent responses, which are associated with increased phosphorylation of the phospholipase C-γ1 site within TrkB receptors and changes of differentiating progenitor subpopulations. Our results show developmental effects of increased calcium influx via L-type Cav channels in FXS neural progenitors.

Flagellar number governs bacterial spreading and transport efficiency.

Peritrichous bacteria synchronize and bundle their flagella to actively swim, while disruption of the bundle leads to a slow motility phase with a weak propulsion. It is still not known whether the number of flagella represents an evolutionary adaptation toward optimizing bacterial navigation. We study the swimming dynamics of differentially flagellated Bacillus subtilis strains in a quasi-two-dimensional system. We find that decreasing the number of flagella N f reduces the average turning angle between two successive run phases and enhances the run time and the directional persistence of the run phase. As a result, having fewer flagella is beneficial for long-distance transport and fast spreading, while having a lot of flagella is advantageous for the processes that require a slower spreading, such as biofilm formation. We develop a two-state random walk model that incorporates spontaneous switchings between the states and yields exact analytical expressions for transport properties, in remarkable agreement with experiments. The results of numerical simulations based on our two-state model suggest that the efficiency of searching and exploring the environment is optimized at intermediate values of N f. The optimal choice of N f, for which the search time is minimized, decreases with increasing the size of the environment in which the bacteria swim.

Changes in external osmolality and ionic composition affect Megaleporinus obtusidens sperm motility

Understanding the effects of environmental factors on sperm motility characteristics can increase artificial reproduction efficiency in species that do not spawn naturally in captivity, such as Megaleporinus obtusidens. This study evaluated the effects of the osmolality (25, 85, 145, 205, 265, and 325 mOsm kg−1) and composition of activating solutions (NaCl, KCl, or fructose) on the percentage of motile sperm, and the swimming velocity and path straightness of M. obtusidens spermatozoa. The concentrations of major ions in the seminal fluid were also assessed and Na+ (74.46 mmol L−1), K+ (37.24 mmol L−1), and Cl− (114.29 mmol L−1) were the most abundant. When the activating solution was hypertonic (325 mOsm kg−1) compared to the seminal fluid (293 mOsm kg−1), sperm motility was completely inhibited. A wide range of osmolalities that initiated sperm motility were identified for all three solutions. Both, the percentage of motile sperm and the motility duration were reduced (P < .05) at extreme osmolalities. At 145 mOsm kg−1, the percentage of motile sperm remained high (>50%) up to 40 s after activation and the motile phase lasted for >50 s, regardless of the activating solution composition. Over the postactivation time, the curvilinear velocity and straightness were similar (P > .05) for fructose and NaCl solutions, whereas KCl solutions induced a higher (P < .05) curvilinear velocity, lower (P < .05) straight-line velocity, and a circular swimming motion in spermatozoa. Our results suggest that a reduction in osmolality, using both non-electrolyte and electrolyte solutions, is the main trigger for the onset of spermatic movement in M. obtusidens sperm.

Effects of beta-sitosterol on isolated human non-pregnant uterus in comparison to prostaglandin E2

Background: Beta-sitosterol (β-sitosterol) is one of the several phytosterols widely studied for its potential to reduce benign prostatic hyperplasia and blood cholesterol levels. Objective: In the present study, the effects of β-sitosterol on spontaneous and agonist-induced contractions in in vitro nonpregnant human uterus with respect to prostaglandin E2(PGE2) were investigated. Materials and Methods: Myometrial strips, measuring approximately 15 mm × 4 mm × 2 mm, were attained from hysterectomy samples of premenopausal women. Longitudinal muscle strips were mounted on tissue baths, under physiological conditions, to measure their isometric contraction. The effects of cumulative amounts of β-sitosterol on spontaneous motility in the absence and presence of prazosin, atropine, fulvestran, indomethacin, or ethylenediaminetetraacetic acid (EDTA), and on agonist-induced motor activity, were examined. Results: On strips in the follicular phase, both β-sitosterol (1–100 μg/ml) and PGE2(0.1–10 μg/ml) increase, in a concentration-dependent manner, muscular basic tonus and amplitude and frequency of spontaneous uterine contractions; whereas on strips obtained during periovulatory phase, β-sitosterol and PGE2cause inhibition of uterine motility. For contractile response, the effective concentrations (EC50) were 47.8 μg/ml and 5.19 μg/ml, respectively. Unlike indomethacin, the tissue pretreatment with prazosin, fulvestran, atropine, or ethylenediaminetetraacetic acid did not affect the contractile uterine responses to β-sitosterol. Furthermore, the β-sitosterol was able to potentiate the contractile response induced by acetylcholine and vasopressin. Conclusions: These observations suggest that β-sitosterol may be a useful modulator of the uterine motility during menstrual cycle, facilitating female fertility.

ДІАГНОСТИКА ХРОНІЧНОГО ПАНКРЕАТИТУ І ФУНКЦІОНАЛЬНИХ ПОРУШЕНЬ ПІДШЛУНКОВОЇ ЗАЛОЗИ ПРИ СУПУТНІХ ЗАХВОРЮВАННЯХ ДВАНАДЦЯТИПАЛОЇ КИШКИ

В роботі представлені результати дослідження тонічної і функціональної активності підшлункової залози (ПЗ) в міжтравний період (МТП) у хворих на хронічний панкреатит (ХП) при супутній патології дванадцятипалої кишки (ДПК).Мета – визначити стан підшлункової залози в МТП у хворих на ХП при захворюваннях ДПК з використанням методу поліметрії і ультрасонографії в режимі моніторингу. Результати. Дослідження за вказаною методикою показало, що розміри і ехоструктура ПЗ непостійні як у хворих, так і у здорових осіб. Вони змінюються залежно від фаз МТМ ДПК. У здорових залоза буває найбільшою в ІІ фазу нерегулярної моторики, що триває (56,8±4,1) хвилин, в ІІІ фазу – ритмічних скорочень, що триває (7,6±0,8) хвилин, вона буває найменшою, а ехоструктура її підсилюється. Коливання розмірів ПЗ при цьому складають: в ділянці головки – (3,0±0,1) мм, в області тіла – 6,0±0,4 мм і в області хвоста – 7,0±0,2 мм. У хворих на ХП коливання змін розмірів і ехоструктури залози залежать від тяжкості та тривалості основного захворювання, а також від типу супутньої дискінезії ДПК. При гіпомоторній дискінезії, характерній для АД і ХПДП, вираженої динаміки в змінах розмірів та ехоструктури залози ми не спостерігали (Р&lt;0,05). У хворих на ХД з гіпермоторним типом дискінезії ДПК виявлено зменшення розмірів ПЗ і підсилення її ехоструктури в ІІ і ІІІ фази моторики (Р&lt;0,05). У хворих на ХП, особливо при тяжкому перебігу захворювання і тривалості захворювання більше 15 років, коливання змін розмірів і ехоструктури ПЗ за фазами МТМ не виявилось (Р&lt;0,05). Дані ультрасонографії ПЗ у динаміці відповідали формі й стадії ХП.Використання в дослідженні зазначеної методики дозволило виявити ХП лише у 29 % обстежених, підтвердивши його наявність клінічними, інструментальними і лабораторними методами; у інших 71,0 % обстежених, які в поліклініці при направленні в клініку класифікувалися як хворі на «хронічний панкреатит», зміни з боку ПЗ розглядати як функціональні, вторинні, клінічно відповідні гіпо- або гіпермоторній дискінезії ДПК.Висновки. 1. Показники фазної тонічної активності ПЗ в МТП є важливими критеріями в диференціальній діагностиці органічних уражень ПЗ, зокрема при ХП, і функціонального її стану, відповідно фазам моторики і типу дискінезії ДПК.2. Для одержання об’єктивної інформації про стан підшлункової залози при ультрасонографії слід враховувати тривалість МТП (в середньому 90 хвилин), фазні зміни розмірів і ехоструктури ПЗ, та проводити дослідження тричі з інтервалом не менше 30 хвилин.