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1.
Sci Rep ; 14(1): 10863, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740831

RESUMO

Ticks are blood-feeding arthropods that require heme for their successful reproduction. During feeding they also acquire pathogens that are subsequently transmitted to humans, wildlife and/or livestock. Understanding the regulation of tick midgut is important for blood meal digestion, heme and nutrient absorption processes and for aspects of pathogen biology in the host. We previously demonstrated the activity of tick kinins on the cognate G protein-coupled receptor. Herein we uncovered the physiological role of the kinin receptor in the tick midgut. A fluorescently-labeled kinin peptide with the endogenous kinin 8 sequence (TMR-RK8), identical in the ticks Rhipicephalus microplus and R. sanguineus, activated and labeled the recombinant R. microplus receptor expressed in CHO-K1 cells. When applied to the live midgut the TMR-RK8 labeled the kinin receptor in muscles while the labeled peptide with the scrambled-sequence of kinin 8 (TMR-Scrambled) did not. The unlabeled kinin 8 peptide competed TMR-RK8, decreasing confocal microscopy signal intensity, indicating TMR-RK8 specificity to muscles. TMR-RK8 was active, inducing significant midgut peristalsis that was video-recorded and evaluated with video tracking software. The TMR-Scrambled peptide used as a negative control did not elicit peristalsis. The myotropic function of kinins in eliciting tick midgut peristalsis was established.


Assuntos
Cricetulus , Cininas , Neuropeptídeos , Peristaltismo , Animais , Cininas/metabolismo , Células CHO , Neuropeptídeos/metabolismo , Neuropeptídeos/genética , Músculos/metabolismo , Músculos/fisiologia , Carrapatos/metabolismo , Carrapatos/fisiologia , Rhipicephalus/metabolismo , Rhipicephalus/fisiologia , Rhipicephalus/genética , Proteínas de Artrópodes/metabolismo , Proteínas de Artrópodes/genética
2.
BMJ Case Rep ; 17(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627049

RESUMO

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare, congenital functional intestinal obstruction, characterised by megacystis (bladder distention in the absence of mechanical obstruction), microcolon and intestinal hypoperistalsis (dysmotility).We are reporting a case of a female child with normal antenatal course who presented with recurrent episodes of abdominal distension since the second day of life and underwent negative exploratory laparotomy on multiple occasions. She also had urinary retention with a grossly distended bladder, requiring drainage by clean intermittent catheterisation. Surgical procedures for bowel decompression, including gastrostomy and ileostomy, were carried out without success. Genetic analysis revealed a mutation in the human smooth muscle (enteric) gamma-actin gene (ACTG2 gene), clinching the diagnosis of MMIHS. The patient was managed with parenteral nutrition and prokinetic medications and tolerated jejunostomy feeds for a brief period before she succumbed to the illness.Female neonates or infants presenting with abdominal distension and dilated urinary tract should be investigated for MMIHS early on. A timely diagnosis will enable the early involvement of a multidisciplinary team to provide the best options available for management.


Assuntos
Anormalidades Múltiplas , Colo/anormalidades , Doenças Fetais , Pseudo-Obstrução Intestinal , Bexiga Urinária/anormalidades , Retenção Urinária , Lactente , Recém-Nascido , Criança , Humanos , Feminino , Gravidez , Pseudo-Obstrução Intestinal/diagnóstico , Pseudo-Obstrução Intestinal/terapia , Pseudo-Obstrução Intestinal/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/terapia , Anormalidades Múltiplas/genética , Colo/cirurgia , Peristaltismo
3.
Medicine (Baltimore) ; 103(17): e37101, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669387

RESUMO

This study aimed to investigate the relationship between endoscopic gastroesophageal valve grading and mean nocturnal baseline impedance (MNBI) and postreflux swallow-induced peristaltic wave index (PSPWI) in patients with gastroesophageal reflux disease (GERD). A total of 120 patients diagnosed with GERD disease were included in the study. According to the classification of endoscopic gastroesophageal valves, the patients were divided into 5 groups, group 1 as baseline group, and Group 2-4 as Hill grade I-IV. Basic information about the patients was collected, including age and gender. The mean nocturnal baseline impedance and creep wave index induced by swallowing after rumination were measured by high resolution creep measurement technique. Through statistical analysis, the relationship between valve classification and observation index was discussed. In terms of MNBI, impedance values gradually decreased with increasing valve classification. The average impedance of the Grade 1 group was 23.5 mm Hg/cm2, while the average impedance of the Grade 5 group was 15.2 mm Hg/cm2. This reduction showed a significant decreasing trend (P < .001). In addition, in terms of the peristaltic wave index caused by swallowing after regurgitation, the peristaltic wave index gradually increased with the increase of valve classification. The mean index in the Grade 1 group was 1.8 beats/min, while the mean index in the Grade 5 group was 3.6 beats/min. This increase showed a significant positive relationship (P < .001). Endoscopic gastroesophageal valve grading was significantly correlated with MNBI and PSPWI in patients with GERD. These observations can serve as useful tools for assessing the severity of GERD and monitoring disease progression.


Assuntos
Deglutição , Impedância Elétrica , Refluxo Gastroesofágico , Peristaltismo , Humanos , Refluxo Gastroesofágico/fisiopatologia , Refluxo Gastroesofágico/diagnóstico , Feminino , Masculino , Pessoa de Meia-Idade , Peristaltismo/fisiologia , Deglutição/fisiologia , Adulto , Idoso , Junção Esofagogástrica/fisiopatologia , Índice de Gravidade de Doença
4.
Proc Inst Mech Eng H ; 238(5): 529-536, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38519860

RESUMO

In the past studies, the resistance of magnetically controlled capsules running through the small intestine has been modeled assuming that the small intestine was a circular tube with a constant diameter. Peristalsis is an important character of the human gastrointestinal system, and it would result in some changes in the diameter of the intestine, meaning that the existing resistance models would no longer be applicable. In this paper, based on the assumption that intestinal peristalsis is actually a sinusoidal wave, a resistance model of the capsule running in the peristaltic intestine is established, and then it is validated experimentally. The model provides a realistic foundation for the optimization and control of the magnetically controlled endoscopy.


Assuntos
Cápsulas Endoscópicas , Modelos Biológicos , Peristaltismo , Peristaltismo/fisiologia , Humanos , Intestino Delgado/fisiologia
5.
Dig Dis Sci ; 69(5): 1714-1721, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38528208

RESUMO

BACKGROUND: The post-reflux swallow-induced peristaltic wave (PSPW) brings salivary bicarbonate to neutralize residual distal esophageal mucosal acidification. AIMS: To determine if reduced saliva production and esophageal body hypomotility would compromise PSPW-induced pH recovery in the distal esophagus. METHODS: In this multicenter retrospective cross-sectional study, patients with confirmed Sjogren's syndrome and scleroderma/mixed connective tissue disease (MCTD) who underwent high resolution manometry (HRM) and ambulatory pH-impedance monitoring off antisecretory therapy were retrospectively identified. Patients without these disorders undergoing HRM and pH-impedance monitoring for GERD symptoms were identified from the same time-period. Acid exposure time, numbers of reflux episodes and PSPW, pH recovery with PSPW, and HRM metrics were extracted. Univariate comparisons and multivariable analysis were performed to determine predictors of pH recovery with PSPW. RESULTS: Among Sjogren's syndrome (n = 34), scleroderma/MCTD (n = 14), and comparison patients with reflux symptoms (n = 96), the scleroderma/MCTD group had significantly higher AET, higher prevalence of hypomotility, lower detected reflux episodes, and very low numbers of PSPW (p ≤ 0.004 compared to other groups). There was no difference in pH-impedance metrics between Sjogren's syndrome, and comparison patients (p ≥ 0.481). Proportions with complete pH recovery with PSPW was lower in Sjogren's patients compared to comparison reflux patients (p = 0.009), predominantly in subsets with hypomotility (p < 0.001). On multivariable analysis, diagnosis of Sjogren's syndrome, scleroderma/MCTD or neither (p = 0.014) and esophageal hypomotility (p = 0.024) independently predicted lack of complete pH recovery with PSPW, while higher total reflux episodes trended (p = 0.051). CONCLUSIONS: Saliva production and motor function are both important in PSPW related pH recovery.


Assuntos
Monitoramento do pH Esofágico , Esôfago , Refluxo Gastroesofágico , Peristaltismo , Saliva , Síndrome de Sjogren , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Refluxo Gastroesofágico/fisiopatologia , Refluxo Gastroesofágico/metabolismo , Refluxo Gastroesofágico/diagnóstico , Estudos Transversais , Peristaltismo/fisiologia , Síndrome de Sjogren/fisiopatologia , Síndrome de Sjogren/metabolismo , Saliva/metabolismo , Idoso , Esôfago/fisiopatologia , Esôfago/metabolismo , Manometria , Deglutição/fisiologia , Concentração de Íons de Hidrogênio , Adulto , Escleroderma Sistêmico/fisiopatologia , Escleroderma Sistêmico/metabolismo
6.
J Math Biol ; 88(3): 37, 2024 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430250

RESUMO

This study discusses non-steady effects encountered in peristaltic flows in oesophagus. The purpose of this communication is to evolve a mechanism to diagnose tumor in an oesophagus mathematically. The tumor is modelled by generic bump function of certain height and width. The method of solution follows long wavelength and low-Reynolds number approximations for unsteady flow, while integrations have been performed numerically in order to plot graphs, which reveal various characteristics of the flow. The goal is to assess how pressure varies across the tumor's width. The spatial, as well as temporal, dependence of pressure has been studied in the laboratory frame of reference. The pressure distribution for tumor-infected oesophagus is compared with that of normal oesophagus. An intensified pressure is obtained in the presence of tumor. The interruption while swallowing through benign oesophageal tumor is confirmed by an abrupt pressure rise across the tumor's width. Tumor position also plays a significant role whether it is at contraction or relaxation of walls. Additionally, wall-shear-stress, volumetric flow rate and streamlines have also been described and compared with that without tumor growth. The expressions corresponding to all the physical quantities are computed numerically. Further, this model may also be implemented to the two-dimensional channel flow for an industrial application.


Assuntos
Deglutição , Neoplasias , Humanos , Modelos Teóricos , Esôfago , Peristaltismo
8.
Biol Pharm Bull ; 47(2): 373-382, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38325854

RESUMO

Patients with diarrhea-predominant irritable bowel syndrome (IBS-D) show excessive peristalsis, and antispasmodic agents may be useful therapeutic agents. There are few reports on the use of Kampo medicines for the treatment of IBS-D. Shakuyakukanzoto (SKT) is a Kampo medicine that is effective against abdominal pain. We examined the relationship between SKT and intestinal peristalsis in an animal model and a prospective study. In the animal model, SKT and its components were administered from the serosal side of the colon and colonic peristalsis was evaluated using intraluminal pressure and spatiotemporal mapping before and after the administration of SKT and its components. In this clinical trial, we used abdominal ultrasonography (US) to obtain long-axis images of the sigmoid colon of 11 patients. The frequency of intestinal peristalsis was measured using US in five patients with SKT and six patients without medication after the ingestion of a test meal. The primary outcome was the frequency of peristalsis. The Clinical Trial Registry Website (Trial No. UMIN-CTR; UMIN000051547). In the animal model, peony did not suppress peristalsis frequency, but SKT (p = 0.005) and glycyrrhiza (p = 0.001) significantly suppressed peristalsis frequency compared with saline and peony. Among the glycyrrhiza components, glycycoumarin and isoliquiritigenin suppressed the peristalsis frequency compared to dimethyl sulfoxide (control) (p = 0.001, 0.01, respectively). In a clinical trial, peristalsis was significantly suppressed after oral administration in patients taking SKT (p = 0.03). Administration of SKT was found to inhibit colonic peristalsis, with glycicumarin and isoliquiritigenin being particularly relevant among its components.


Assuntos
Chalconas , Síndrome do Intestino Irritável , Humanos , Animais , Peristaltismo , Estudos Prospectivos , Modelos Animais , Diarreia
9.
Int J Gynaecol Obstet ; 165(2): 666-671, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38205860

RESUMO

OBJECTIVE: The non-pregnant uterus shows an intrinsic contractility pattern, actively involved in early reproductive processes. Uterine contractility is characterized by endometrial waves that originate from the junctional zone and varies throughout the menstrual cycle due to fluctuations in the concentrations of hormones. The aim of this study was to compare the uterine contractility patterns in the periovulatory phase in a group of patients with isolated adenomyosis and a group of healthy women using transvaginal ultrasound (TVUS). METHODS: From March 2019 to March 2021, we enrolled consecutive nulliparous patients in the periovulatory phase of the menstrual cycle, divided in patients with isolated adenomyosis (group A, n = 18) and healthy patients in the control group (group B, n = 18). Patients who met the inclusion criteria underwent TVUS for the study of uterine contractility: the uterus was scanned on sagittal plane for 3 min and all the movies were recorded. Then, static images and video were evaluated offline and the uterine contractility patterns were defined. RESULTS: The patients belonging to the study group had a higher incidence of painful symptoms (dysmenorrhea, 6.11 ± 2.81 vs 1.39 ± 2.17; chronic pelvic pain, 2.56 ± 3.01 vs 0.39 ± 1.04) and a larger uterine volume (137.48 ± 117.69 vs 74.50 ± 27.58 cm3; P = 0.04). Regarding the uterine contractility, a statistically significant difference was observed about the retrograde patterns (group A, 27.8% vs group B, 72.2%, P < 0.01) and opposing (group A, 38.9% vs, group B, 5.6%, P = 0.02). CONCLUSION: The study confirms the presence of altered uterine peristalsis in the periovulatory phase in patients with adenomyosis. The abnormal uterine peristalsis could lead to both structural and functional changes, which are the basis of the clinical manifestations of adenomyosis and the perpetuation of the anatomical damage.


Assuntos
Adenomiose , Humanos , Feminino , Adenomiose/diagnóstico por imagem , Peristaltismo , Útero/diagnóstico por imagem , Endométrio , Dismenorreia/etiologia
10.
Sci Adv ; 10(1): eadj7067, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38181085

RESUMO

Biologic drugs hold immense promise for medical treatments, but their oral delivery remains a daunting challenge due to the harsh digestive environment and restricted gastrointestinal absorption. Here, inspired by the porcupinefish's ability to inflate itself and deploy its spines for defense, we proposed an intestinal microneedle robot designed to absorb intestinal fluids for rapid inflation and inject drug-loaded microneedles into the insensate intestinal wall for drug delivery. Upon reaching the equilibrium volume, the microneedle robot leverages rhythmic peristaltic contraction for mucosa penetration. The robot's barbed microneedles can then detach from its body during peristaltic relaxation and retain in the mucosa for drug releasing. Extensive in vivo experiments involving 14 minipigs confirmed the effectiveness of the intestinal peristalsis for microrobot actuation and demonstrated comparable insulin delivery efficacy to subcutaneous injection. The ingestible peristalsis-actuated microneedle robots may transform the oral administration of biologic drugs that primary relies on parenteral injection currently.


Assuntos
Produtos Biológicos , Robótica , Animais , Suínos , Peristaltismo , Produtos Biológicos/farmacologia , Porco Miniatura , Digestão
11.
Korean J Gastroenterol ; 83(1): 23-27, 2024 Jan 25.
Artigo em Coreano | MEDLINE | ID: mdl-38268165

RESUMO

Achalasia is an esophageal motility disorder characterized by loss of esophageal peristalsis and impaired relaxation of the lower esophageal sphincter. Patients with achalasia often complain of persistent symptoms for several years before diagnosis. On the other hand, achalasia diagnosed as a sudden esophageal food impaction is uncommon, and no report has been issued on the diagnosis and successful treatment of achalasia in a 95-year-old patient. We report a case of achalasia diagnosed by high-resolution esophageal manometry and timed barium esophagography after food material removal by endoscopy in a 95-year-old woman who visited the hospital due to sudden esophageal food impaction and was successfully treated by endoscopic balloon dilatation.


Assuntos
Acalasia Esofágica , Transtornos da Motilidade Esofágica , Idoso de 80 Anos ou mais , Feminino , Humanos , Acalasia Esofágica/diagnóstico , Nonagenários , Hospitais , Peristaltismo
12.
Biomed Phys Eng Express ; 10(2)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38227968

RESUMO

Ureters are essential components of the urinary system and play a crucial role in the transportation of urine from the kidneys to the bladder. In the current study, a three-dimensional ureter is modelled. A series of peristaltic waves are made to travel on the ureter wall to analyse and measure parameter effects such as pressure, velocity, gradient pressure, and wall shear at different time steps. The flow dynamics in the ureters are thoroughly analysed using the commercially available ANSYS-CFX software. The maximum pressure is found in the triple wave at the ureteropelvic junction and maximum velocity is observed in the single and double wave motion due to the contraction produced by the peristalsis motion. The pressure gradient is maximum at the inlet of the ureter during the single bolus motion. The contraction produces a high jet of velocity due to neck formation and also helps in urine trapping in the form of a bolus, which leads to the formation of reverse flow. Due to the reduction in area, shear stress builds on the ureter wall. The high shear stress may rupture the junctions in the ureter.


Assuntos
Ureter , Peristaltismo , Modelos Biológicos , Pressão , Bexiga Urinária
13.
Neurogastroenterol Motil ; 36(4): e14746, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38263867

RESUMO

BACKGROUND: The impact of esophageal dysmotility among patients with post-fundoplication esophageal symptoms is not fully understood. This study aimed to investigate secondary peristalsis and esophagogastric junction (EGJ) opening biomechanics using functional lumen imaging probe (FLIP) panometry in symptomatic post-fundoplication patients. METHODS: Eighty-seven adult patients post-fundoplication who completed FLIP for symptomatic esophageal evaluation were included. Secondary peristaltic contractile response (CR) patterns and EGJ opening metrics (EGJ distensibility index (EGJ-DI) and maximum EGJ diameter) were evaluated on FLIP panometry and analyzed against high-resolution manometry (HRM), patient-reported outcomes, and fundoplication condition seen on esophagram and/or endoscopy. KEY RESULTS: FLIP CR patterns included 14 (16%) normal CR, 30 (34%) borderline CR, 28 (32%) impaired/disordered CR, 13 (15%) absent CR, and 2 (2%) spastic reactive CR. Compared with normal and borderline CRs (i.e., CR patterns with distinct, antegrade peristalsis), patients with impaired/disordered and absent CRs demonstrated significantly greater time since fundoplication (2.4 (0.6-6.8) vs. 8.9 (2.6-14.5) years; p = 0.002), greater esophageal body width on esophagram (n = 50; 2.3 (2.0-2.8) vs. 2.9 (2.4-3.6) cm; p = 0.013), and lower EGJ-DI (4.3 (2.7-5.4) vs. 2.6 (1.7-3.7) mm2/mmHg; p = 0.001). Intact fundoplications had significantly higher rates of normal CRs compared to anatomically abnormal (i.e., tight, disrupted, slipped, herniated) fundoplications (9 (28%) vs. 5 (9%); p = 0.032), but there were no differences in EGJ-DI or EGJ maximum diameter. CONCLUSIONS & INFERENCES: Symptomatic post-fundoplication patients were characterized by frequent abnormal secondary peristalsis after fundoplication, potentially worsening with time after fundoplication or related to EGJ outflow resistance.


Assuntos
Acalasia Esofágica , Fundoplicatura , Adulto , Humanos , Fundoplicatura/efeitos adversos , Acalasia Esofágica/diagnóstico , Peristaltismo , Junção Esofagogástrica , Manometria/métodos , Endoscopia Gastrointestinal
14.
Neurourol Urodyn ; 43(1): 258-266, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37961019

RESUMO

PURPOSE: The etiology of ureteral dilation in primary nonrefluxing, nonobstructing megaureters is still not well understood. Impaired ureteral peristalsis has been theorized as one of the contributing factors. However, ureteral peristalsis and its "normal" function is not well defined. In this study, using mathematical modeling techniques, we aim to better understand how ureteral peristalsis works. This is the first model to consider clinically observed, back-and-forth, cyclic wall longitudinal motion during peristalsis. We hypothesize that dysfunctional ureteral peristalsis, caused by insufficient peristaltic amplitudes (e.g., circular muscle dysfunction) and/or lack of ureteral wall longitudinal motion (e.g., longitudinal muscle dysfunction), promotes peristaltic reflux (i.e., retrograde flow of urine during an episode of peristalsis) and may result in urinary stasis, urine accumulation, and consequent dilation. METHODS: Based on lubrication theory in fluid mechanics, we developed a two-dimensional (planar) model of ureteral peristalsis. In doing so, we treated ureteral peristalsis as an infinite train of sinusoidal waves. We then analyzed antegrade and retrograde flows in the ureter under different bladder-kidney differential pressure and peristalsis conditions. RESULTS: There is a minimum peristaltic amplitude required to prevent peristaltic reflux. Ureteral wall longitudinal motion decreases this minimum required amplitude, increasing the nonrefluxing range of peristaltic amplitudes. As an example, for a normal bladder-kidney differential pressure of 5 cmH2 O, ureteral wall longitudinal motion increases nonrefluxing range of peristaltic amplitude by 65%. Additionally, ureteral wall longitudinal motion decreases refluxing volumetric flow rates. For a similar normal bladder pressure example of 5 cmH2 O, refluxing volumetric flow rate decreases by a factor of 18. Finally, elevated bladder pressure, not only increases the required peristaltic amplitude for reflux prevention but it increases maximum refluxing volumetric flow rates. For the case without wall longitudinal motion, as bladder-kidney differential pressure increases from 5 to 40 cmH2 O, minimum required peristaltic amplitude to prevent reflux increases by 40% while the maximum refluxing volumetric flow rate increases by approximately 100%. CONCLUSION: The results presented in this study show how abnormal ureteral peristalsis, caused by the absence of wall longitudinal motion and/or lack of sufficient peristaltic amplitudes, facilitates peristaltic reflux and retrograde flow. We theorize that this retrograde flow can lead to urinary stasis and urine accumulation in the ureters, resulting in ureteral dilation seen on imaging studies and elevated infection risk. Our results also show how chronically elevated bladder pressures are more susceptible to such refluxing conditions that could lead to ureteral dilation.


Assuntos
Ureter , Obstrução Ureteral , Humanos , Peristaltismo/fisiologia , Dilatação , Ureter/fisiologia , Bexiga Urinária
15.
Biotechnol Bioeng ; 121(3): 1118-1143, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38151924

RESUMO

A novel bioreactor simulating human colonic conditions for in vitro cultivation of intestinal microbiota is presented. The PEristaltic mixed Tubular bioReactor (PETR) is modular designed and periodically kneaded to simulate intestinal peristalsis. The reactor is introduced, characterized from a bioprocess engineer's perspective and discussed in its ability to mimic colon conditions. PETR provides physiological temperature and appropriate anaerobic conditions, simulates intestinal peristalsis, and has a mean residence time of 32.8 ± 0.8 h comparable to the adult human colon. The single-tube design enables a time-constant and longitudinally progressive pH gradient from 5.5 to 7.0. Using a dialysis liquid containing high molecular weight polyethylene glycol, the integrated dialysis system efficiently absorbs short chain fatty acids (up to 60%) and water (on average 850 mL d-1 ). Cultivation of a typical gut bacterium (Bifidobacterium animalis) was performed to demonstrate the applicability for controlled microbiota cultivation. PETR is unique in combining simulation of the entire colon, peristaltic mixing, dialytic water and metabolite absorption, and a progressive pH gradient in a single-tube design. PETR is a further step to precise replication of colonic conditions in vitro for reliable and reproducible microbiota research, such as studying the effect of food compounds, prebiotics or probiotics, or the development and treatment of infections with enteric pathogens, but also for further medical applications such as drug delivery studies or to study the effect of drugs on and their degradation by the microbiota.


Assuntos
Colo , Peristaltismo , Adulto , Humanos , Colo/química , Colo/metabolismo , Colo/microbiologia , Prebióticos/análise , Reatores Biológicos , Água/metabolismo
16.
Commun Biol ; 6(1): 1237, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062160

RESUMO

Assessing gastrointestinal motility lacks simultaneous evaluation of intraluminal pressure (ILP), circular muscle (CM) and longitudinal muscle (LM) contraction, and lumen emptying. In this study, a sophisticated machine was developed that synchronized real-time recordings to quantify the intricate interplay between CM and LM contractions, and their timings for volume changes using high-resolution cameras with machine learning capability, the ILP using pressure transducers and droplet discharge (DD) using droplet counters. Results revealed four distinct phases, BPhase, NPhase, DPhase, and APhase, distinguished by pressure wave amplitudes. Fluid filling impacted LM strength and contraction frequency initially, followed by CM contraction affecting ILP, volume, and the extent of anterograde, retrograde, and segmental contractions during these phases that result in short or long duration DD. This comprehensive analysis sheds light on peristalsis mechanisms, understand their sequence and how one parameter influenced the other, offering insights for managing peristalsis by regulating smooth muscle contractions.


Assuntos
Motilidade Gastrointestinal , Peristaltismo , Animais , Camundongos , Peristaltismo/fisiologia , Motilidade Gastrointestinal/fisiologia , Contração Muscular/fisiologia , Intestino Delgado
17.
Neurogastroenterol Motil ; 35(12): e14692, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37845833

RESUMO

BACKGROUND AND AIMS: The distal contractile integral (DCI) quantifies the contractile vigor of primary peristalsis on high-resolution manometry (HRM), whereas no such metric exists for secondary peristalsis on functional lumen imaging probe (FLIP) panometry. This study aimed to evaluate novel FLIP metrics of contraction power and displaced volume in asymptomatic controls and a patient cohort. METHODS: Thirty-five asymptomatic controls and adult patients (with normal esophagogastric junction outflow/opening and without spasm) who completed HRM and FLIP panometry were included. The patient group also completed timed barium esophagram (TBE). Contraction power (estimate of esophageal work over time) and displaced volume (estimate of contraction-associated fluid flow) were computed from FLIP. HRM was analyzed per Chicago Classification v4.0. KEY RESULTS: In controls, median (5th-95th percentile) contraction power was 27 mW (10-44) and displaced volume was 43 mL (17-66). 95 patients were included: 72% with normal motility on HRM, 17% with ineffective esophageal motility (IEM), and 12% with absent contractility. Among patients, DCI was significantly correlated with both contraction power (rho = 0.499) and displaced volume (rho = 0.342); p values < 0.001. Both contraction power and displaced volume were greater in patients with normal motility versus IEM or absent contractility, complete versus incomplete bolus transit, and normal versus abnormal retention on TBE; p values < 0.02. CONCLUSIONS: FLIP panometry metrics of contraction power and displaced volume appeared to effectively quantify peristaltic vigor. These novel metrics may enhance evaluation of esophageal motility with FLIP panometry and provide a reliable surrogate to DCI on HRM.


Assuntos
Transtornos da Motilidade Esofágica , Peristaltismo , Adulto , Humanos , Esôfago/diagnóstico por imagem , Junção Esofagogástrica/diagnóstico por imagem , Contração Muscular , Manometria/métodos , Transtornos da Motilidade Esofágica/diagnóstico
18.
Pflugers Arch ; 475(11): 1315-1327, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37589734

RESUMO

In isolated segments of the rat proximal colon, the dopamine reuptake inhibitor GBR 12909 (GBR) causes a dilatation, while the D1-like receptor antagonist SCH 23390 (SCH) induces a tonic constriction, suggesting that neurally released dopamine tonically stimulates enteric inhibitory efferent neurons. Here, the targets of the enteric dopaminergic neurons were investigated. Cannulated segments of rat proximal colon were bathed in physiological salt solution and luminally perfused with 0.9% saline, while all drugs were applied to the bath. Spatio-temporal maps of colonic motility were constructed from video recordings of peristaltic contractions, and the maximum diameter was measured as an index of colonic contractility. GBR (1 µM)-induced dilatations of colonic segments were prevented by SCH (5 µM), L-nitro arginine (L-NA; 100 µM), a nitric oxide synthase inhibitor, or tetrodotoxin (0.6 µM). In contrast, constrictions induced by a higher concentration of SCH (20 µM) were unaffected by either L-NA or tetrodotoxin. The vasoactive intestinal peptide (VIP) receptor antagonist VIP10-28 (3 µM) or P2Y1 receptor antagonist MRS 2500 (1 µM) had no effect on either the GBR-induced dilatation or the SCH-induced constriction. In colonic segments that had been pretreated with 6-hydroxydopamine (100 µM, 3 h) to deplete enteric dopamine, GBR failed to increase the colonic diameter, while SCH was still capable of constricting colonic segments. Enteric dopaminergic neurons appear to project to nitrergic neurons to dilate the proximal colon by activating neuronal D1-like receptors. In addition, constitutively activated D1-like receptors expressed in cells yet to be determined may provide a tonic inhibition on colonic constrictions.


Assuntos
Dopamina , Neurônios , Ratos , Animais , Dopamina/farmacologia , Tetrodotoxina/farmacologia , Peristaltismo/fisiologia , Arginina/farmacologia , Colo , Motilidade Gastrointestinal
19.
Int J Biol Macromol ; 250: 126155, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549765

RESUMO

The soluble crude polysaccharides from Dioscorea opposita (DOP1 and DOP2) were prepared and characterized. DOP1 and DOP2 obtained carbohydrate (65.71% and 70.18%, respectively), uronic acid (63.71% and 24.84%, respectively) and protein (8.09% and 9.51%, respectively) with molecular weight of 49.24 kDa and 21.62 kDa, respectively. DOP samples were mainly composed of mannose, glucose, galacturonic acid, galactose, and glucuronic acid. The digestibility in vitro, antioxidant activity and intestinal peristalsis effect were then investigated. DOP1 and DOP2 were degraded with decreased molecular weights (39.58 kDa and 18.56 kDa respectively), increased reducing sugar contents (from 16.95% to 19.27%; 12.45% to 15.50% respectively) and free monosaccharides (from 0.89% to 1.42%; 0.90% to 1.14% respectively) after gastric digestion. Both DOP1 and DOP2 were resistant to intestinal digestion, suggesting that DOP samples can be considered as a dietary fiber. Additionally, DOP1 and DOP2 exhibited antioxidant activities positively correlated with the concentration and remained the activities after gastrointestinal digestion in vitro. Furthermore, DOP reduced the fluorescence intensity significantly, indicating DOP can promote the intestinal peristalsis of zebrafish larvae (5 pdf) at 500 µg/mL. Therefore, DOP1 and DOP2 have a better functionality as dietary fibers, including antioxidant activity and intestinal peristalsis promotion, which can be developed as functional foods.


Assuntos
Antioxidantes , Dioscorea , Animais , Antioxidantes/farmacologia , Peixe-Zebra/metabolismo , Dioscorea/metabolismo , Peristaltismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Fibras na Dieta
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