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Biomechanics and Modeling in... Feb 2023A FLIP device gives cross-sectional area along the length of the esophagus and one pressure measurement, both as a function of time. Deducing mechanical properties of...
A FLIP device gives cross-sectional area along the length of the esophagus and one pressure measurement, both as a function of time. Deducing mechanical properties of the esophagus including wall material properties, contraction strength, and wall relaxation from these data are a challenging inverse problem. Knowing mechanical properties can change how clinical decisions are made because of its potential for in-vivo mechanistic insights. To obtain such information, we conducted a parametric study to identify peristaltic regimes by using a 1D model of peristaltic flow through an elastic tube closed on both ends and also applied it to interpret clinical data. The results gave insightful information about the effect of tube stiffness, fluid/bolus density and contraction strength on the resulting esophagus shape through quantitive representations of the peristaltic regimes. Our analysis also revealed the mechanics of the opening of the contraction area as a function of bolus flow resistance. Lastly, we concluded that peristaltic driven flow displays three modes of peristaltic geometries, but all physiologically relevant flows fall into two peristaltic regimes characterized by a tight contraction.
Topics: Deglutition; Muscle Contraction; Esophagus; Peristalsis; Body Fluids
PubMed: 36352039
DOI: 10.1007/s10237-022-01625-x -
Autonomic Neuroscience : Basic &... Oct 2016The primary function of the upper urinary tract is to propel urine and various water-soluble toxic compounds from the kidneys to the bladder for storage and evacuation... (Review)
Review
The primary function of the upper urinary tract is to propel urine and various water-soluble toxic compounds from the kidneys to the bladder for storage and evacuation to maintain body ionic balance and contribute to the regulation of blood volume and pressure. The mechanism by which the upper urinary tract propels urine has long been considered to be myogenic in origin as peristaltic contractions in vivo and in vitro (pyeloureteric peristalsis) propagate in a manner little affected by drugs that block nerve conduction or the sympathetic and parasympathetic transmission. However, it is now well established that the release of intrinsic prostaglandins and neuropeptides from primary sensory nerves (PSNs) helps to maintain pyeloureteric peristalsis. Electrical field stimulation of PSNs evokes species-specific positive inotropic and chronotropic effects that have been attributed to release of excitatory tachykinins superimposed on negative inotropic and chronotropic effects associated with the release of calcitonin gene related peptide (CGRP), a rise in cellular cyclic-adenosine monophosphate (cAMP) and a protein kinase A-dependent activation of glibenclamide-sensitive ATP-dependent K (K) channels. This review summarises the existing evidence of the nervous control of the upper urinary tract and recent evidence suggesting that the autonomic innervation may indirectly modulate pyeloureteric peristalsis via the activation of PSN nicotinic receptors and via the modulation of K7 channels located on interstitial cells within the renal pelvis wall.
Topics: Animals; Autonomic Nervous System; Humans; Kidney Pelvis; Muscle Contraction; Muscle, Smooth; Myocytes, Smooth Muscle; Peristalsis
PubMed: 26278377
DOI: 10.1016/j.autneu.2015.07.425 -
The Korean Journal of Gastroenterology... Feb 2022The Chicago Classification is being revised continuously for the accurate diagnosis of esophageal peristaltic disorders in which the etiology is unclear, and the disease... (Review)
Review
The Chicago Classification is being revised continuously for the accurate diagnosis of esophageal peristaltic disorders in which the etiology is unclear, and the disease behavior is heterogeneous. The ver. 4.0 was recently updated. A representative change in the diagnosis of esophageal peristaltic disorders of the ver. 4.0 showed that the distinction between major and minor disorders was eliminated and was divided into the following four diagnoses: absent contractility, distal esophageal spasm (DES), hypercontractile esophagus (HE), and ineffective esophageal motility. Compared to the ver. 3.0, it recommended a more detailed protocol of high-resolution esophageal manometry and methods of interpreting manometric. In addition, it emphasized the clinically relevant symptoms in diagnosing DES and HE, and presented provocative tests (e.g., multiple rapid swallow and rapid drinking challenge), as well as additional testing, including impedance, timed barium esophagogram and functional lumen imaging probe, which may provide more standardized and rigorous criteria for peristaltic patterns and to minimize the ambiguity in diagnosis. Although it will take time and effort to apply this revised Chicago Classification in clinical practice, it may help diagnose and manage patients with esophageal peristalsis disorder in the future.
Topics: Esophageal Achalasia; Esophageal Motility Disorders; Humans; Manometry; Peristalsis
PubMed: 35232921
DOI: 10.4166/kjg.2022.016 -
Gastrointestinal Endoscopy Clinics of... Oct 2014The Chicago Classification defines esophageal motility disorders in high resolution manometry. This is based on individual scoring of 10 swallows performed in supine... (Review)
Review
The Chicago Classification defines esophageal motility disorders in high resolution manometry. This is based on individual scoring of 10 swallows performed in supine position. Disorders of esophago-gastric junction (EGJ) outflow obstruction are defined by a median integrated relaxation pressure above the limit of normal and divided into 3 achalasia subtypes and EGJ outflow obstruction. Major motility disorders (aperistalsis, distal esophageal spasm, and hypercontractile esophagus) are patterns not encountered in controls in the context of normal EGJ relaxation. Finally with the latest version of the Chicago Classification, only two minor motor disorders are considered: ineffective esophageal motility and fragmented peristalsis.
Topics: Deglutition; Esophageal Motility Disorders; Esophagogastric Junction; Esophagus; Humans; Manometry; Peristalsis
PubMed: 25216902
DOI: 10.1016/j.giec.2014.07.001 -
In Vivo (Athens, Greece) 2023Gastrectomy with lymphadenectomy is a standard treatment for gastric cancer. Anastomotic leakage remains a potentially fatal complication of gastrectomy. Forceful...
BACKGROUND/AIM
Gastrectomy with lymphadenectomy is a standard treatment for gastric cancer. Anastomotic leakage remains a potentially fatal complication of gastrectomy. Forceful stapler extraction may cause anastomotic complications. We focused on the duodenal peristalsis, as we hypothesized that it might cause forceful stapler extraction. We then retrospectively investigated duodenal peristalsis and reviewed videos of Da Vinci system cases to clarify the relationship between peristalsis and anastomotic complications.
PATIENTS AND METHODS
Forty-nine cases with stored videos of laparoscopic surgery using the Da Vinci system from 2015 to March 2021 were included. Peristalsis was defined by repeated contraction and expansion that was clearly visible three or more times in a row. The duodenum was investigated because it is frequently observed during gastrectomy. Suture failure was evaluated in cases with and without peristalsis.
RESULTS
The study population included 49 patients [male, n=32; female, n=17; median age, 71 (42-82) years]. Duodenal peristalsis was observed in 14 (28.6%) cases. Three patients experienced complications. A comparative study of cases with and without complications showed significant peristalsis in cases with complications (p=0.0198).
CONCLUSION
A new definition to evaluate duodenal peristalsis was established. Anastomotic complications were significantly more frequent in cases with peristalsis (p=0.0198). Our results suggest the utility of manual over-sewing or the use of reinforcement material.
Topics: Humans; Male; Female; Aged; Retrospective Studies; Peristalsis; Gastrectomy; Anastomotic Leak; Stomach Neoplasms; Laparoscopy; Sutures
PubMed: 37369506
DOI: 10.21873/invivo.13281 -
Neurogastroenterology and Motility Oct 2023Primary and secondary peristalsis facilitate esophageal bolus transport; however, their relative impact for bolus clearance remains unclear. We aimed to compare primary...
BACKGROUND
Primary and secondary peristalsis facilitate esophageal bolus transport; however, their relative impact for bolus clearance remains unclear. We aimed to compare primary peristalsis and contractile reserve on high-resolution manometry (HRM) and secondary peristalsis on functional lumen imaging probe (FLIP) Panometry with emptying on timed barium esophagogram (TBE) and incorporate findings into a comprehensive model of esophageal function.
METHODS
Adult patients who completed HRM with multiple rapid swallows (MRS), FLIP, and TBE for esophageal motility evaluation and without abnormal esophagogastric junction outflow/opening or spasm were included. An abnormal TBE was defined as a 1-min column height >5 cm. Primary peristalsis and contractile reserve after MRS were combined into an HRM-MRS model. Secondary peristalsis was combined with primary peristalsis assessment to describe a complementary neuromyogenic model.
KEY RESULTS
Of 89 included patients, differences in rates of abnormal TBEs were observed with primary peristalsis classification (normal: 14.3%; ineffective esophageal motility: 20.0%; absent peristalsis: 54.5%; p = 0.009), contractile reserve (present: 12.5%; absent: 29.3%; p = 0.05), and secondary peristalsis (normal: 9.7%; borderline: 17.6%; impaired/disordered: 28.6%; absent contractile response: 50%; p = 0.039). Logistic regression analysis (akaike information criteria, area under the receiver operating curve) demonstrated that the neuromyogenic model (80.8, 0.83) had a stronger relationship predicting abnormal TBE compared to primary peristalsis (81.5, 0.82), contractile reserve (86.8, 0.75), or secondary peristalsis (89.0, 0.78).
CONCLUSIONS AND INFERENCES
Primary peristalsis, contractile reserve, and secondary peristalsis were associated with abnormal esophageal retention as measured by TBE. Added benefit was observed when applying comprehensive models to incorporate primary and secondary peristalsis supporting their complementary application.
Topics: Adult; Humans; Barium; Peristalsis; Esophagus; Esophagogastric Junction; Muscle Contraction; Manometry; Esophageal Achalasia; Esophageal Motility Disorders
PubMed: 37417394
DOI: 10.1111/nmo.14638 -
Cells, Tissues, Organs 2023Peristalsis is a nuanced mechanical stimulus comprised of multi-axial strain (radial and axial strain) and shear stress. Forces associated with peristalsis regulate...
Peristalsis is a nuanced mechanical stimulus comprised of multi-axial strain (radial and axial strain) and shear stress. Forces associated with peristalsis regulate diverse biological functions including digestion, reproductive function, and urine dynamics. Given the central role peristalsis plays in physiology and pathophysiology, we were motivated to design a bioreactor capable of holistically mimicking peristalsis. We engineered a novel rotating screw-drive based design combined with a peristaltic pump, in order to deliver multi-axial strain and concurrent shear stress to a biocompatible polydimethylsiloxane (PDMS) membrane "wall." Radial indentation and rotation of the screw drive against the wall demonstrated multi-axial strain evaluated via finite element modeling. Experimental measurements of strain using piezoelectric strain resistors were in close alignment with model-predicted values (15.9 ± 4.2% vs. 15.2% predicted). Modeling of shear stress on the "wall" indicated a uniform velocity profile and a moderate shear stress of 0.4 Pa. Human mesenchymal stem cells (hMSCs) seeded on the PDMS "wall" and stimulated with peristalsis demonstrated dramatic changes in actin filament alignment, proliferation, and nuclear morphology compared to static controls, perfusion, or strain, indicating that hMSCs sensed and responded to peristalsis uniquely. Lastly, significant differences were observed in gene expression patterns of calponin, caldesmon, smooth muscle actin, and transgelin, corroborating the propensity of hMSCs toward myogenic differentiation in response to peristalsis. Collectively, our data suggest that the peristalsis bioreactor is capable of generating concurrent multi-axial strain and shear stress on a "wall." hMSCs experience peristalsis differently than perfusion or strain, resulting in changes in proliferation, actin fiber organization, smooth muscle actin expression, and genetic markers of differentiation. The peristalsis bioreactor device has broad utility in the study of development and disease in several organ systems.
Topics: Humans; Peristalsis; Biomimetics; Actins; Cell Differentiation; Bioreactors
PubMed: 35008089
DOI: 10.1159/000521752 -
American Journal of Physiology.... Nov 2021Gastric peristalsis is critically dependent on an underlying electrical conduction system. Recent years have witnessed substantial progress in clarifying the operations... (Review)
Review
Gastric peristalsis is critically dependent on an underlying electrical conduction system. Recent years have witnessed substantial progress in clarifying the operations of this system, including its pacemaking units, its cellular architecture, and slow-wave propagation patterns. Advanced techniques have been developed for assessing its functions at high spatiotemporal resolutions. This review synthesizes and evaluates this progress, with a focus on human and translational physiology. A current conception of the initiation and conduction of slow-wave activity in the human stomach is provided first, followed by a detailed discussion of its organization at the cellular and tissue level. Particular emphasis is then given to how gastric electrical disorders may contribute to disease states. Gastric dysfunction continues to grow in their prevalence and impact, and while gastric dysrhythmia is established as a clear and pervasive feature in several major gastric disorders, its role in explaining pathophysiology and informing therapy is still emerging. New insights from high-resolution gastric mapping are evaluated, together with historical data from electrogastrography, and the physiological relevance of emerging biomarkers from body surface mapping such as retrograde propagating slow waves. Knowledge gaps requiring further physiological research are highlighted.
Topics: Animals; Biological Clocks; Cell Communication; Gastric Emptying; Gastroparesis; Humans; Interstitial Cells of Cajal; Membrane Potentials; Peristalsis; Stomach; Stomach Diseases
PubMed: 34549598
DOI: 10.1152/ajpgi.00065.2021 -
Revista Espanola de Enfermedades... Jun 2023A 24-year-old male presented with an asymptomatic right perirenal cyst that was detected on ultrasound performed during a physical screening. Abdominal computed...
A 24-year-old male presented with an asymptomatic right perirenal cyst that was detected on ultrasound performed during a physical screening. Abdominal computed tomography showed a hypodense cystic mass between the liver and right kidney. Peristalsis of the cystic mass was observed via multi-phase CT scan, including plain scan, arterial phase, venous phase and delayed phase. The mass was completely resected by laparoscopy.
Topics: Male; Humans; Young Adult; Adult; Peristalsis; Tomography, X-Ray Computed; Ultrasonography; Laparoscopy; Cysts
PubMed: 37232158
DOI: 10.17235/reed.2023.9721/2023 -
American Journal of Physiology.... Feb 2021The goal of this study was to conceptualize and compute measures of "mechanical work" done by the esophagus using data generated during functional lumen imaging probe...
The goal of this study was to conceptualize and compute measures of "mechanical work" done by the esophagus using data generated during functional lumen imaging probe (FLIP) panometry and compare work done during secondary peristalsis among patients and controls. Eighty-five individuals were evaluated with a 16-cm FLIP during sedated endoscopy, including asymptomatic controls ( = 14) and those with achalasia subtypes I, II, and III ( = 15, each); gastroesophageal reflux disease (GERD; = 13); eosinophilic esophagitis (EoE; = 9); and systemic sclerosis (SSc; = 5). The FLIP catheter was positioned to have its distal segment straddling the esophagogastric junction (EGJ) during stepwise distension. Two metrics of work were assessed: "active work" (during bag volumes ≤ 40 mL where contractility generates substantial changes in lumen area) and "work capacity" (for bag volumes ≥ 60 mL when contractility cannot substantially alter the lumen area). Controls showed median [interquartile range (IQR)] of 7.3 (3.6-9.2) mJ of active work and 268.6 (225.2-332.3) mJ of work capacity. Patients with all achalasia subtypes, GERD, and SSc showed lower active work done than controls ( ≤ 0.003). Patients with achalasia subtypes I and II, GERD, and SSc had lower work capacity compared with controls ( < 0.001, 0.004, 0.04, and 0.001, respectively). Work capacity was similar between controls and patients with achalasia type III and EoE. Mechanical work of the esophagus differs between healthy controls and patient groups with achalasia, EoE, SSc, and GERD. Further studies are needed to fully explore the utility of this approach, but these work metrics would be valuable for device design (artificial esophagus), to measure the efficacy of peristalsis, to gauge the physiological state of the esophagus, and to comment on its pumping effectiveness. Functional lumen imaging probe (FLIP) panometry assesses esophageal response to distension and provides a simultaneous assessment of pressure and dimension during contractility. This enables an objective assessment of "mechanical work" done by the esophagus. Eighty-five individuals were evaluated, and two work metrics were computed for each subject. Controls showed greater values of work compared with individuals with achalasia, gastroesophageal reflux disease (GERD), and systemic sclerosis (SSc). These values can quantify the mechanical behavior of the distal esophagus and assist in the estimation of muscular integrity.
Topics: Adult; Aged; Case-Control Studies; Esophageal Achalasia; Esophagus; Female; Gastroesophageal Reflux; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Peristalsis; Pressure; Scleroderma, Systemic
PubMed: 33174457
DOI: 10.1152/ajpgi.00324.2020