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1.
Phys Rev Lett ; 129(6): 067001, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-36018650

RESUMEN

Using sound velocity and attenuation measurements in high magnetic fields, we identify a new transition in the vortex lattice state of La_{2-x}Sr_{x}CuO_{4}. The transition, observed in magnetic fields exceeding 35 T and temperatures far below zero field T_{c}, is detected in the compression modulus of the vortex lattice, at a doping level of x=p=0.17. Our theoretical analysis based on Eilenberger's theory of the vortex lattice shows that the transition corresponds to the long-sought 45° rotation of the square vortex lattice, predicted to occur in d-wave superconductors near a van Hove singularity.

2.
Phys Rev Lett ; 128(20): 207002, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35657867

RESUMEN

In the cuprates, high-temperature superconductivity, spin-density-wave order, and charge-density-wave (CDW) order are intertwined, and symmetry determination is challenging due to domain formation. We investigated the CDW in the prototypical cuprate La_{1.88}Sr_{0.12}CuO_{4} via x-ray diffraction employing uniaxial pressure as a domain-selective stimulus to establish the unidirectional nature of the CDW unambiguously. A fivefold enhancement of the CDW amplitude is found when homogeneous superconductivity is partially suppressed by magnetic field. This field-induced state provides an ideal search environment for a putative pair-density-wave state.

3.
Int Urogynecol J ; 33(6): 1557-1565, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34936023

RESUMEN

INTRODUCTION AND HYPOTHESIS: Urinary incontinence is common postpartum. Our aims were to assess whether antenatal exercise including pelvic floor muscle training (PFMT) has long-term effects on urinary incontinence (UI) and to explore factors associated with UI 7 years postpartum. METHODS: A follow-up of a two-centre randomized controlled trial performed at St. Olavs Hospital and Stavanger University Hospital, Norway. In the original trial women were randomized to a 12-week structured exercise protocol including PFMT or standard antenatal care during pregnancy. Link to an electronic questionnaire was sent by postal mail 7 years postpartum. Prevalence of UI was assessed with Sandvik severity index and compared between groups. Factors associated with UI were studied using multivariable logistic regression analysis. RESULTS: The response rate was 35% (298/855). UI was reported by 78 (51%) in the intervention group and 63 (57%) in the control group (p = 0.539). In the multivariable logistic regression analyses, women with UI at inclusion had a five-fold increase in odds of UI at 7 years (OR 5.4, 95% CI 2.6, 11.5). Engaging in regular exercise was not significantly associated with UI at 7 years; however, UI was associated with lower exercise intensity (OR 2.4, 95% CI 1.2, 4.6). CONCLUSIONS: We found no group differences of antenatal exercise including PFMT on UI after 7 years among the responders. UI in pregnancy increased the risk of long-term UI. Regular exercise was not associated with UI at 7 years; however, women with UI were more than twice as likely to exercise at lower intensity than continent women.


Asunto(s)
Diafragma Pélvico , Incontinencia Urinaria , Terapia por Ejercicio/métodos , Femenino , Estudios de Seguimiento , Humanos , Embarazo , Atención Prenatal , Resultado del Tratamiento , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/terapia
4.
Phys Rev Lett ; 124(20): 207005, 2020 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-32501068

RESUMEN

The discovery of charge-density-wave-related effects in the resonant inelastic x-ray scattering spectra of cuprates holds the tantalizing promise of clarifying the interactions that stabilize the electronic order. Here, we report a comprehensive resonant inelastic x-ray scattering study of La_{2-x}Sr_{x}CuO_{4} finding that charge-density wave effects persist up to a remarkably high doping level of x=0.21 before disappearing at x=0.25. The inelastic excitation spectra remain essentially unchanged with doping despite crossing a topological transition in the Fermi surface. This indicates that the spectra contain little or no direct coupling to electronic excitations near the Fermi surface, rather they are dominated by the resonant cross section for phonons and charge-density-wave-induced phonon softening. We interpret our results in terms of a charge-density wave that is generated by strong correlations and a phonon response that is driven by the charge-density-wave-induced modification of the lattice.

5.
Phys Rev Lett ; 124(18): 187002, 2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32441965

RESUMEN

We use resonant inelastic x-ray scattering to investigate charge-stripe correlations in La_{1.675}Eu_{0.2}Sr_{0.125}CuO_{4}. By differentiating elastic from inelastic scattering, it is demonstrated that charge-stripe correlations precede both the structural low-temperature tetragonal phase and the transport-defined pseudogap onset. The scattering peak amplitude from charge stripes decays approximately as T^{-2} towards our detection limit. The in-plane integrated intensity, however, remains roughly temperature independent. Therefore, although the incommensurability shows a remarkably large increase at high temperature, our results are interpreted via a single scattering constituent. In fact, direct comparison to other stripe-ordered compounds (La_{1.875}Ba_{0.125}CuO_{4}, La_{1.475}Nd_{0.4}Sr_{0.125}CuO_{4}, and La_{1.875}Sr_{0.125}CuO_{4}) suggests a roughly constant integrated scattering intensity across all these compounds. Our results therefore provide a unifying picture for the charge-stripe ordering in La-based cuprates. As charge correlations in La_{1.675}Eu_{0.2}Sr_{0.125}CuO_{4} extend beyond the low-temperature tetragonal and pseudogap phase, their emergence heralds a spontaneous symmetry breaking in this compound.

6.
Lett Appl Microbiol ; 69(3): 175-180, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31220345

RESUMEN

Although norovirus (NoV) is the major cause of gastroenteritis, with the largest number of NoV food poisoning cases in Japan, limited information is available regarding NoV detection in food. This study aimed to detect NoV in food samples during the 2015-2016 suspected foodborne outbreaks in Tokyo; 352 food samples from 64 NoV food poisoning outbreaks were collected. Bacterial culturing was performed for sample pretreatment and real-time reverse transcription polymerase chain reaction was conducted for NoV screening. The NoV detection rate was 1·7% (6/352). NoV-positive food samples included leftover boxed lunch, mackerel fillet (foodstuff), aburi salmon slice (partially seared salmon slice), raw tuna as a chirashizushi ingredient, raw amberjack as a sushi topping and ice for drinks. Since fresh fish as sushi toppings or ingredients and ice were consumed without heating, they may present a higher risk of viral infection. NoV-positive food samples were obtained from five outbreaks, wherein food handlers were NoV-positive in four. Each partial VP1 sequence from food samples matched completely with those in NoV-positive individuals and food handlers. Hence, food handlers play a potentially important role in food-based NoV transmission in all five outbreaks; therefore, hygiene education among them is essential to prevent NoV foodborne outbreaks. SIGNIFICANCE AND IMPACT OF THE STUDY: Significance and Impact of the Study: Norovirus (NoV) is a leading cause of foodborne outbreak in Japan. The most frequent route of transmission in NoV foodborne outbreaks is secondary contamination via infected food handlers. However, limited information is available regarding NoV contamination in food samples. This study reports the detection of NoV in food samples to elucidate the source and route of NoV infection leading to outbreaks for 2 years in Tokyo. Our data potentially contribute to education and the development of safe food-handling strategies among food handlers and employees in the food industry through elucidation of risk factors associated with NoV contamination.


Asunto(s)
Infecciones por Caliciviridae/transmisión , Enfermedades Transmitidas por los Alimentos/virología , Gastroenteritis/virología , Norovirus/aislamiento & purificación , Alimentos Crudos/virología , Animales , Infecciones por Caliciviridae/virología , Brotes de Enfermedades , Peces/virología , Manipulación de Alimentos , Humanos , Japón , Norovirus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Tokio
7.
Med Oral Patol Oral Cir Bucal ; 22(3): e349-e353, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28390120

RESUMEN

BACKGROUND: To elucidate the significance of absorbable surgical sutures in the occurrence of stitch abscess after surgery in patients with oral squamous cell carcinoma (SCC). MATERIAL AND METHODS: The subjects were 251 patients who underwent excision and/or reconstruction and/or neck dissection for oral SCC using absorbable surgical sutures. Detection rates and characteristics of patients with stitch abscess were retrospectively evaluated by comparing between our present and previous data. RESULTS: There was only one stitch abscess among the 251 patients. A significant difference in the incidence of stitch abscess was found between the present data and our previous data. Of course, no significant correlations were found between the occurrence of stitch abscess using absorbable surgical sutures and the various factors seen in our previous analysis. CONCLUSIONS: A complete switch of surgical sutures from silk to absorbable surgical sutures is needed for surgery in patients with oral SCC.


Asunto(s)
Absceso/prevención & control , Carcinoma de Células Escamosas/cirugía , Neoplasias de la Boca/cirugía , Infección de la Herida Quirúrgica/prevención & control , Suturas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Materiales Biocompatibles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Adulto Joven
8.
Med Oral Patol Oral Cir Bucal ; 21(3): e341-8, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27031062

RESUMEN

BACKGROUND: 18F-fluoro-2-deoxy-D-glucose (18F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18F-FDG accumulation in neck-related muscles of patients after ND for oral cancer. MATERIAL AND METHODS: 18F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers. RESULTS: According to the extent of ND of cervical lymph nodes, the rate of patients with 18F-FDG-PET-positive areas increased in the trapezius, sternocleidomastoid, and posterior neck muscles of the surgical and/or non-surgical sides. In addition, SUVmax of 18F-FDG-PET-positive areas in the trapezius and sternocleidomastoid muscles were increased according to the extent of the ND. CONCLUSIONS: In evaluating 18F-FDG accumulations after ND for oral cancers, we should pay attention to the 18F-FDG distributions in neck-related muscles including the non-surgical side as false-positive findings.


Asunto(s)
Fluorodesoxiglucosa F18/farmacocinética , Neoplasias de la Boca/diagnóstico por imagen , Disección del Cuello , Radiofármacos/farmacocinética , Humanos , Metástasis Linfática , Neoplasias de la Boca/patología , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X
9.
Osteoporos Int ; 26(7): 1997-2006, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26037792

RESUMEN

UNLABELLED: There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ), because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce how to provide preoperative labeling of the viable bone with minocycline bone fluorescence technique (MBFT) by using VELscope® and investigate histopathologically. INTRODUCTION: The American Association of Oral and Maxillofacial Surgeons (AAOMS) and the Japanese Society of Oral and Maxillofacial Surgeons (JSOMS) now recommend a more conservative treatment strategy. There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ) because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce a mechanism providing preoperative labeling of a viable bone using minocycline bone fluorescence technique (MBFT) with VELscope® and to histopathologically investigate. METHODS: This report describes a surgical technique used in six patients with BRONJ who underwent jawbone resection under minocycline bone fluorescence imaging using VELscope®. Subsequently, we investigated and compared the clinical findings using VELscope® and histopathological findings. RESULTS: Histopathological examinations showed that the non-fluorescent moiety was consistent with the BRONJ lesions. CONCLUSIONS: The surgical treatments that were exactly performed using MBFT with VELscope® offered successful management of BRONJ. This bone fluorescence helped to define the margins of resection, thus improving surgical therapy for extended osteonecrosis.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos/diagnóstico , Osteonecrosis de los Maxilares Asociada a Difosfonatos/cirugía , Cuidados Intraoperatorios/métodos , Imagen Óptica/métodos , Anciano , Anciano de 80 o más Años , Osteonecrosis de los Maxilares Asociada a Difosfonatos/patología , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/administración & dosificación , Difosfonatos/efectos adversos , Esquema de Medicación , Femenino , Humanos , Mandíbula/patología , Osteotomía Mandibular/métodos , Maxilar/patología , Osteotomía Maxilar/métodos , Persona de Mediana Edad , Minociclina , Imagen Óptica/instrumentación
10.
Int J Biol Macromol ; 261(Pt 1): 129550, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38244734

RESUMEN

The enzyme α-Galactosidase (α-D-galactoside galactohydrolase [EC 3.2.1.22]) is an exoglycosidase that hydrolyzes the terminal α-galactosyl moieties of glycolipids and glycoproteins. It is ubiquitous in nature and possesses extensive applications in the food, pharma, and biotechnology industries. The present study aimed to purify α-galactosidase from Klebsiella pneumoniae, a bacterium isolated from the human oral cavity. The purification steps involved ammonium sulfate precipitation (70 %), dialysis, ion exchange chromatography using a DEAE-cellulose column, and affinity monolith chromatography. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis was used to determine the molecular weight of the purified enzyme. The kinetic constants, Michaelis constant (Km) and maximal velocity (Vmax), for this enzyme were determined by using p-nitrophenyl-α-D-galactopyranoside as substrate. The results showed that the purification fold, specific activity, and yield were 126.52, 138.58 units/mg, and 21.5 %, respectively. The SDS-PAGE showed that the molecular weight of the purified enzyme was 75 kDa. The optimum pH and temperature of the purified α-galactosidase were detected at pH 6.0 and 50 °C, respectively. The kinetic constants, Michaelis constant (Km) and maximal velocity (Vmax), for this enzyme were 4.6 mM and 769.23 U/ml, respectively. α-galactosidase from Klebsiella pneumoniae was purified and characterized. (SDS-PAGE) analysis showed that the purified enzyme appeared as single band with a molecular weight of 75 kDa.


Asunto(s)
Klebsiella pneumoniae , alfa-Galactosidasa , Humanos , alfa-Galactosidasa/química , Klebsiella pneumoniae/metabolismo , Diálisis Renal , Temperatura , Cromatografía de Afinidad , Concentración de Iones de Hidrógeno , Peso Molecular , Electroforesis en Gel de Poliacrilamida , Cinética
11.
Gene Ther ; 20(8): 816-23, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23344066

RESUMEN

The development of a safe and reproducible gene delivery system is an essential step toward the clinical application of the hydrodynamic gene delivery (HGD) method. For this purpose, we have developed a novel electric power-driven injection system called the HydroJector-EM, which can replicate various time-pressure curves preloaded into the computer program before injection. The assessment of the reproducibility and safety of gene delivery system in vitro and in vivo demonstrated the precise replication of intravascular time-pressure curves and the reproducibility of gene delivery efficiency. The highest level of luciferase expression (272 pg luciferase per mg of proteins) was achieved safely using the time-pressure curve, which reaches 30 mm Hg in 10 s among various curves tested. Using this curve, the sustained expression of a therapeutic level of human factor IX protein (>500 ng ml(-1)) was maintained for 2 months after the HGD of the pBS-HCRHP-FIXIA plasmid. Other than a transient increase in liver enzymes that recovered in a few days, no adverse events were seen in rats. These results confirm the effectiveness of the HydroJector-EM for reproducible gene delivery and demonstrate that long-term therapeutic gene expression can be achieved by automatic computer-controlled hydrodynamic injection that can be performed by anyone.


Asunto(s)
Factor IX/genética , Técnicas de Transferencia de Gen , Vectores Genéticos , Animales , Expresión Génica , Humanos , Hidrodinámica , Inyecciones , Hígado/metabolismo , Luciferasas/metabolismo , Ratas
12.
NPJ Quantum Mater ; 8(1): 7, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38666240

RESUMEN

In high-temperature cuprate superconductors, stripe order refers broadly to a coupled spin and charge modulation with a commensuration of eight and four lattice units, respectively. How this stripe order evolves across optimal doping remains a controversial question. Here we present a systematic resonant inelastic x-ray scattering study of weak charge correlations in La2-xSrxCuO4 and La1.8-xEu0.2SrxCuO4. Ultra high energy resolution experiments demonstrate the importance of the separation of inelastic and elastic scattering processes. Long-range temperature-dependent stripe order is only found below optimal doping. At higher doping, short-range temperature-independent correlations are present up to the highest doping measured. This transformation is distinct from and preempts the pseudogap critical doping. We argue that the doping and temperature-independent short-range correlations originate from unresolved electron-phonon coupling that broadly peaks at the stripe ordering vector. In La2-xSrxCuO4, long-range static stripe order vanishes around optimal doping and we discuss both quantum critical and crossover scenarios.

13.
Nat Commun ; 13(1): 1795, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379813

RESUMEN

Static stripe order is detrimental to superconductivity. Yet, it has been proposed that transverse stripe fluctuations may enhance the inter-stripe Josephson coupling and thus promote superconductivity. Direct experimental studies of stripe dynamics, however, remain difficult. From a strong-coupling perspective, transverse stripe fluctuations are realized in the form of dynamic "kinks"-sideways shifting stripe sections. Here, we show how modest uniaxial pressure tuning reorganizes directional kink alignment. Our starting point is La1.88Sr0.12CuO4 where transverse kink ordering results in a rotation of stripe order away from the crystal axis. Application of mild uniaxial pressure changes the ordering pattern and pins the stripe order to the crystal axis. This reordering occurs at a much weaker pressure than that to detwin the stripe domains and suggests a rather weak transverse stripe stiffness. Weak spatial stiffness and transverse quantum fluctuations are likely key prerequisites for stripes to coexist with superconductivity.

15.
Phys Rev Lett ; 105(17): 176401, 2010 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-21231061

RESUMEN

We discovered the chirality of charge-density waves (CDW) in 1T-TiSe2 by using STM and time-domain optical polarimetry. We found that the CDW intensity becomes Ia1∶Ia2∶Ia3 = 1∶0.7 ± 0.1∶0.5 ± 0.1, where Ia(i) (i=1,2,3) is the amplitude of the tunneling current contributed by the CDWs. There were two states, in which the three intensity peaks of the CDW decrease clockwise and anticlockwise. The chirality in CDW results in the threefold symmetry breaking. Macroscopically, twofold symmetry was indeed observed in optical measurement. We propose the new generalized CDW chirality H(CDW) ≡ q1·(q2×q3), where q(i) are the CDW q vectors, which is independent of the symmetry of components. The nonzero H(CDW)-the triple-q vectors do not exist in an identical plane in the reciprocal space-should induce a real-space chirality in CDW system.

16.
Colorectal Dis ; 12(10 Online): e320-5, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19863598

RESUMEN

AIM: Acute haemorrhagic rectal ulcer (AHRU) is characterized by sudden onset of painless and massive rectal bleeding in elderly bedridden patients who have serious illness. Endoscopic diagnosis and management of AHRU is, however, still controversial. We retrospectively investigated 95 AHRU patients to elucidate the clinical characteristics, endoscopic findings and haemostatic strategies. METHOD: Between January 1999 and March 2007, 95 patients were diagnosed with AHRU in our hospital. Medical records and colonoscopy files were reviewed. Clinical features, colonoscopic findings, haemostatic treatment and outcome of the patients were evaluated. RESULTS: Eighty per cent of the patients were bedridden at the onset. The most frequent underlying disorder was cerebrovascular disease (36.8%). Hypoalbuminaemia (< 3.5 g/dl) was seen in 92.6% of the patients. Endoscopic findings of AHRU were classified as circumferential ulcer (41.1%), linear or nearly round small ulcer(s) (44.2%), circumferential and small ulcer(s) (7.4%) and Dieulafoy-like ulcer (7.4%). Primary endoscopic haemostatic treatment was performed in 45.3% of cases. Recurrent bleeding occurred in 24.2% of patients. Permanent haemostasis was achieved by secondary endoscopic treatment in 82.6% of re-bleeding patients. CONCLUSION: Understanding the typical clinical and endoscopic findings and careful endoscopic examination are important for the accurate diagnosis of AHRU, and endoscopic haemostatic therapy may be effective for bleeding patients.


Asunto(s)
Hemorragia Gastrointestinal/patología , Hemorragia Gastrointestinal/terapia , Hemostasis Endoscópica/métodos , Enfermedades del Recto/patología , Enfermedades del Recto/terapia , Úlcera/patología , Úlcera/terapia , Anciano , Colonoscopía , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Hipoalbuminemia/complicaciones , Masculino , Enfermedades del Recto/complicaciones , Recurrencia , Estudios Retrospectivos , Úlcera/complicaciones
17.
Kyobu Geka ; 63(8 Suppl): 719-23, 2010 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-20715447

RESUMEN

Completion pneumonectomy (CP) is defined as the operation intended to remove the reminder of the lung after a previous operation. The indications of CP include both benign and malignant diseases and it is more demanding technical procedure with high morbidity and mortality compared to standardized pneumonectomy. In this article, we described our preferable procedures for CP, preoperative evaluation and consideration, surgical technique, management of bronchial stump, and postoperative management. CP should be performed by skilled surgeons and surgeons should know whether they have enough skills and experiences to perform CP.


Asunto(s)
Neoplasias Pulmonares/cirugía , Neumonectomía/métodos , Humanos , Neoplasia Residual/cirugía , Reoperación
18.
Kyobu Geka ; 63(5): 426-9, 2010 May.
Artículo en Japonés | MEDLINE | ID: mdl-20446616

RESUMEN

We report a case of anterior mediastinal lipoma. A 71-year-old female was admitted for cough. A fat density tumor from anterior mediastinum to left thoracic cavity was found by chest X-ray, chest computed tomography (CT) and magnetic resonance imaging (MRI). Defect of left dorsal diaphragm was suspected and there was a possibility that the tumor was connected to retroperitoneum. Under the preoperative diagnosis of a benign huge mediastinal lipoma, we conducted an operation. At 1st, we observed by thoracoscopy and made sure that the mass was primary anterior mediastinal tumor and not connected to retroperitoneum. Through the median sternotomy, we completely resected the tumor with thymus. The tumor showed 27 cm in diameter, and histopathological diagnosis of the tumor was benign lipoma. Lipoma of the mediastinum is very rare and about 0.3% of all mediastinal tumors. It is sometimes difficult to distinguish huge lipoma from liposarcoma only by clinical examinations such as CT scan or MRI. We evaluated the condition of the tumor by thoracoscopic observation, and the tumor was safely and completely resected by median sternotomy.


Asunto(s)
Lipoma/cirugía , Neoplasias del Mediastino/cirugía , Anciano , Femenino , Humanos , Lipoma/diagnóstico , Neoplasias del Mediastino/diagnóstico
19.
Int J Oral Maxillofac Surg ; 49(4): 432-441, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31451304

RESUMEN

The objective was to introduce a new technique for visualizing the three-dimensional (3D) movements of velopharyngeal-related muscles using high-speed cine-magnetic resonance imaging (MRI) based on T2-weighted sequences. The evaluation of phonation- and water swallowing-related events was performed in 11 healthy subjects. Specifically, whether cine-MRI could precisely visualize normal velopharyngeal function during these two events was examined. The 3D movements of the soft palate, superior pharyngeal constrictor muscles, and levator veli palatini muscles were visualized in all 11 subjects. A noteworthy finding was that the magnetic resonance signals of the superior constrictor pharyngeal muscles and the levator veli palatini muscles were significantly higher during phonation and during water swallowing than at rest. This initial study suggests that the 3D movements of velopharyngeal-related muscles can be successfully and precisely visualized without side effects. The magnetic resonance signal changes seen in the superior pharyngeal constrictor and levator veli palatini muscles using the technique described here should be useful to develop better methods of evaluation of velopharyngeal function.


Asunto(s)
Insuficiencia Velofaríngea , Humanos , Imagen por Resonancia Magnética , Músculos Palatinos , Paladar Blando , Músculos Faríngeos
20.
J Cell Biol ; 91(2 Pt 1): 524-30, 1981 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7198127

RESUMEN

The mode of action of cytochalasin B was examined in vitro using bile canaliculus-enriched plasma membrane fractions isolated from rat liver. The pericanalicular microfilaments, which are mainly actin filaments and which are normally attached to the canalicular membranes, were dissociated from the membranes by cytochalasin B treatment. A microfilamentous network was found in the supernate of the cytochalasin B treatment. A microfilamentous network was found in the supernate of the cytochalasin-treated specimens and a number of polypeptides, of which a polypeptide corresponding in molecular weight to actin was a notable member. These results suggest that actin filaments become detached from the canaliculus membranes by cytochalasin B.


Asunto(s)
Membrana Celular/ultraestructura , Citocalasina B/farmacología , Citoesqueleto/efectos de los fármacos , Actinas/análisis , Animales , Canalículos Biliares/ultraestructura , Sistema Libre de Células , Citoesqueleto/análisis , Citoesqueleto/ultraestructura , Masculino , Ratas , Ratas Endogámicas
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