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1.
J Gastroenterol ; 59(5): 361-375, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38472375

RESUMEN

BACKGROUND: Achalasia is an esophageal motility disorder with an unknown etiology. We aimed to determine the pathogenesis of achalasia by studying alterations in esophageal smooth muscle contraction and the associated inflammatory response, and evaluate the role of esophageal microbiota in achalasia development. METHODS: We analyzed esophageal mucosa and lower esophageal sphincter (LES) samples, obtained from patients with type II achalasia who underwent peroral endoscopic myotomy. Esophageal conditioned media obtained from patients were transferred into the mouse esophagus to determine whether the esophageal intraluminal environment is associated with achalasia. RESULTS: Approximately 30% of 20-kDa myosin light chains (LC20) was phosphorylated in LES from the control group under resting and stimulated conditions, whereas less than 10% of LC20 phosphorylation was detected in achalasia under all conditions. The hypophosphorylation of LC20 in achalasia was associated with the downregulation of the myosin phosphatase-inhibitor protein CPI-17. Th17-related cytokines, including IL-17A, IL-17F, IL-22, and IL-23A, were significantly upregulated in achalasia. α-Diversity index of esophageal microbiota and the proportion of several microbes, including Actinomyces and Dialister, increased in achalasia. Actinomyces levels positively correlated with IL-23A levels, whereas Dialister levels were positively associated with IL-17A, IL-17F, and IL-22 levels. Esophageal IL-17F levels increased in mice after oral administration of the conditioned media. CONCLUSIONS: In LES of patients with achalasia, hypophosphorylation of LC20, a possible cause of impaired contractility, was associated with CPI-17 downregulation and an increased Th17-related immune response. The esophageal intraluminal environment, represented by the esophageal microbiota, could be associated with the development and exacerbation of achalasia.


Asunto(s)
Acalasia del Esófago , Animales , Humanos , Ratones , Medios de Cultivo Condicionados , Esfínter Esofágico Inferior , Inmunidad , Interleucina-17 , Fosforilación , Cadenas Ligeras de Miosina
2.
Langmuir ; 35(32): 10397-10404, 2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31317747

RESUMEN

The understanding of polymer dewetting on solid surfaces is significant in both fundamental polymer physics and practical film technologies. When liquid crystalline (LC) polymers are dewetted, LC ordering is involved in the dewetting process. Here, we report on the characteristic dewetting processes of a diblock copolymer composed of a cyanobiphenyl side chain liquid crystalline polymer (SCLCP) block connected with polystyrene (PS) taking place on a PS base film. Thin films of the block copolymer were prepared by the water-floating method onto the PS film, and the dewetting process is observed in a softened state above the glass transition temperature of the PS. At the smectic A phase temperature of the SCLCP block, the dewetted surface layer generated a flat unique fingering pattern leading to a monolayered (two-dimensional) high-density LC polymer brush through the LC ordering. The important role of the anchoring PS block on the base PS film surface is suggested for the formation of highly stretched LC polymer brush. Above the isotropization temperature, in contrast, ordinary three-dimensional droplet morphologies with smooth round edges were observed. By photo-cross-linking the base PS film, the lateral diffusion rate was significantly reduced. This can be applied to an entropy-driven morphology patterning via dewetting. The polymer brush formation and its spatial controls are expected to provide new opportunities for the modification strategies of polymer surfaces.

3.
Angew Chem Int Ed Engl ; 55(45): 14028-14032, 2016 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-27726257

RESUMEN

High-density polymer brushes on substrates exhibit unique properties and functions stemming from the extended conformations due to the surface constraint. To date, such chain organizations have been mostly attained by synthetic strategies of surface-initiated living polymerization. We show herein a new method to prepare a high-density polymer brush architecture using surface segregation and self-assembly of diblock copolymers containing a side-chain liquid-crystalline polymer (SCLCP). The surface segregation is attained from a film of an amorphous base polymer (polystyrene, PS) containing a minor amount of a SCLCP-PS diblock copolymer upon annealing above the glass-transition temperature. The polystyrene portion of the diblock copolymer can work as a laterally mobile anchor for the favorable self-assembly on the polystyrene base film.

4.
J Gastroenterol Hepatol ; 31(6): 1133-40, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26670865

RESUMEN

BACKGROUND AND AIM: Esophageal motility disorders (EMDs) affect coordinated esophageal contractility. Recent developments in high-resolution manometry have improved diagnosis of EMDs; however, the etiology of EMDs remains to be determined. This study aimed to determine which clinical characteristics are associated with esophageal motility. METHODS: From May 2013 to July 2014, 97 patients (54 women, 43 men; age, 16-89 years) with suspected EMDs were assessed by high-resolution manometry in Kyushu University Hospital. Esophageal motility was evaluated by measuring the distal contractile integral (DCI), basal lower esophageal sphincter pressure, and integrated relaxation pressure (IRP). Data on age, gender, body mass index (BMI), Brinkman Index, and blood tests were retrospectively collected and analyzed. RESULTS: Fifty patients were diagnosed as normal, nine with achalasia, twelve with esophagogastric junction outflow obstruction, four with distal esophageal spasm, one with jackhammer esophagus, six with absent peristalsis, ten with frequent failed peristalsis, and five with weak peristalsis. The median DCI was 1229.0 mmHg-s-cm, the median basal lower esophageal sphincter pressure was 25.3 mmHg, and the median IRP was 9.6 mmHg. Patients with major motility disorders were excluded from analysis. By multivariate regression analysis, BMI (P = 0.029) and total cholesterol (P = 0.023) were negatively associated with DCI, while BMI (P = 0.007) was negatively associated with IRP and glucose (P = 0.044) was positively associated with IRP. CONCLUSIONS: Both BMI and total cholesterol could be highly predictive factors for esophageal body contractility, while BMI and glucose could be predictive factors for lower esophageal sphincter contractile function.


Asunto(s)
Trastornos de la Motilidad Esofágica/diagnóstico , Esófago/fisiopatología , Motilidad Gastrointestinal , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Glucemia/análisis , Índice de Masa Corporal , Colesterol/sangre , Complicaciones de la Diabetes/diagnóstico , Complicaciones de la Diabetes/etiología , Complicaciones de la Diabetes/fisiopatología , Trastornos de la Motilidad Esofágica/etiología , Trastornos de la Motilidad Esofágica/fisiopatología , Esfínter Esofágico Inferior/fisiopatología , Femenino , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/complicaciones , Hipercolesterolemia/diagnóstico , Japón , Masculino , Manometría , Persona de Mediana Edad , Análisis Multivariante , Contracción Muscular , Relajación Muscular , Obesidad/complicaciones , Obesidad/diagnóstico , Valor Predictivo de las Pruebas , Presión , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
5.
Nature ; 514(7522): 339-42, 2014 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-25296250

RESUMEN

Classical novae are the most common astrophysical thermonuclear explosions, occurring on the surfaces of white dwarf stars accreting gas from companions in binary star systems. Novae typically expel about 10(-4) solar masses of material at velocities exceeding 1,000 kilometres per second. However, the mechanism of mass ejection in novae is poorly understood, and could be dominated by the impulsive flash of thermonuclear energy, prolonged optically thick winds or binary interaction with the nova envelope. Classical novae are now routinely detected at gigaelectronvolt γ-ray wavelengths, suggesting that relativistic particles are accelerated by strong shocks in the ejecta. Here we report high-resolution radio imaging of the γ-ray-emitting nova V959 Mon. We find that its ejecta were shaped by the motion of the binary system: some gas was expelled rapidly along the poles as a wind from the white dwarf, while denser material drifted out along the equatorial plane, propelled by orbital motion. At the interface between the equatorial and polar regions, we observe synchrotron emission indicative of shocks and relativistic particle acceleration, thereby pinpointing the location of γ-ray production. Binary shaping of the nova ejecta and associated internal shocks are expected to be widespread among novae, explaining why many novae are γ-ray emitters.

6.
Artículo en Inglés | MEDLINE | ID: mdl-22255540

RESUMEN

A non-constraint cardiac vibration, respiration, and body movement monitoring system has been developed. The sensor system is designed to be easily installable under an existing bed mattress. The sensor consists of a 40-kHz ultrasound transmitter and receiver pair. The transmitted ultrasound is reflected on the mattress' undersurface, and the amplitude of the received ultrasonic wave is modulated by the shape of the mattress, and parameters such as respiration, cardiac vibration, and movement. The physiological parameters can be extracted from the reflected ultrasound by an envelope detection circuit. To confirm the accuracy of the developed system, measurements were performed on 6 normal male subjects aged 25.0 ± 6.7 years, using 2 pocket spring coil mattresses and a polyurethane foam mattress. The results revealed that the physiological parameters were monitored with an 84.2% average accuracy for all mattresses when the subjects lay on the beds in the supine, lateral, and prone positions.


Asunto(s)
Actigrafía/instrumentación , Lechos , Electrocardiografía/instrumentación , Frecuencia Cardíaca/fisiología , Monitoreo Ambulatorio/instrumentación , Oscilometría/instrumentación , Frecuencia Respiratoria/fisiología , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Transductores
7.
Biomed Sci Instrum ; 46: 87-93, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20467077

RESUMEN

UNLABELLED: An ultrasonic physical and care monitoring system has been developed for monitoring the physiological parameters of body movement, heart contraction, and respiration of patients on low-repulsion, anti-decubitus (anti-bedsore) hospital beds. These beds, of several designs, are intended to reduce pressure on the body surface of immobilized patients, in order to prevent decubitus ulcers, which are often fatal. Since low-repulsion mattresses lack conventional springs, padding and air space, this system employs a polyvinyl chloride tube under the mattress, which has a 40 kHz ultrasonic transmitter and receiver at its ends. The shape of the tube is altered by body, heart and respiratory movements, which modulate the complex diffusion of the ultrasonic energy in the tube. As a result, the amplitude of the received ultrasonic signal is movement-modulated. This received signal is then demodulated and low, high and band pass filtered, to yield the three separate patient movement parameters. These are recorded and can be real-time computer analyzed, to activate alarms if the patient has not moved, or not been moved by the staff, within programmable time limits. These data may also be employed to indicate relative patient medical condition. A major system advantage is that it does not require any body-attached sensors. KEYWORDS: Ultrasound, cardiac pulse, respiration, body movement, low-repulsion mattress, decubitus ulcer.

8.
Artículo en Inglés | MEDLINE | ID: mdl-19964384

RESUMEN

We have developed a remote system for monitoring heart rate, respiration rate and movement behavior of at-home elderly people who are living alone. The system consists of a 40 kHz ultrasonic transmitter and receiver, linear integrated circuits, a low-power 8-bit single chip microcomputer and an Internet server computer. The 40 kHz ultrasonic transmitter and receiver are installed into a bed mattress. The transmitted signal diffuses into the bed mattress, and the amplitude of the received ultrasonic wave is modulated by the shape of the mattress and parameters such as respiration, cardiac vibration and movement. The modulated ultrasonic signal is received and demodulated by an envelope detection circuit. Low, high and band pass filters separate the respiration, cardiac vibration and movement signals, which are fed into the microcontroller and digitized at a sampling rate of 50 Hz by 8-bit A/D converters. The digitized data are sent to the server computer as a serial signal. This computer stores the data and also creates a graphic chart of the latest hour. The person's family or caregiver can download this chart via the Internet at any time.


Asunto(s)
Lechos , Frecuencia Cardíaca/fisiología , Movimiento/fisiología , Respiración , Telemetría/instrumentación , Adulto , Humanos , Internet , Masculino , Persona de Mediana Edad , Diseño de Software , Adulto Joven
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