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1.
J Neurogastroenterol Motil ; 30(2): 229-235, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38576372

RESUMEN

Background/Aims: Although certain allergic diseases have been reported to be associated with the prevalence of functional dyspepsia (FD) and irritable bowel syndrome (IBS), it is unclear whether the presence of multiple allergic diseases further increases the prevalence of FD and IBS. The aim of this study is to determine this issue in young people. Methods: A cohort of 8923 Japanese university students was enrolled and diagnoses of FD and IBS were confirmed using Rome III criteria. Allergic disorders diagnosed at medical institutions were obtained by means of a self-administered questionnaire. Results: The prevalence of FD, IBS, and their overlap was found to be 1.9%, 6.5%, and 1.1%, respectively. Pollen allergy was independently positively correlated with FD, IBS, and overlap of FD and IBS. Allergic rhinitis was positively linked to IBS. Drug allergy was positively associated with FD. The presence of multiple allergic diseases was positively correlated with FD and IBS (FD: adjusted OR for 2 allergic diseases: 1.95 [95% CI, 1.24-2.98], P for trend = 0.003; and IBS: adjusted OR for 1 allergic disease: 1.40 [95% CI, 1.15-1.69], 2 allergic diseases 1.47 [95% CI, 1.12-1.91], and 3 or more allergic diseases: 2.22 [95% CI, 1.45-3.28], P for trend = 0.001). Additionally, the concomitant existence of multiple allergic diseases was also demonstrated to have a trend that correlated with the overlap of FD and IBS (P for trend = 0.018). Conclusion: Allergic disease multimorbidity is positively correlated with the prevalence of FD and IBS in a young population.

2.
Respirol Case Rep ; 8(7): e00643, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32832087

RESUMEN

Clinicians should be careful when examining a case with endobronchial hamartoma with concurrent malignant disease because radiographic imaging and symptoms cannot clearly differentiate between both diseases.

3.
Opt Express ; 28(12): 17457-17467, 2020 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-32679953

RESUMEN

This paper proposes an electrothermally-actuated circular pyramidal kirigami microscanner with a millimeter-range low-power lens drive for endoscopic biomedical applications. A variation of Japanese origami art, kirigami involves creation of out-of-plane structures by paper cutting and folding. The proposed microscanner is composed of freestanding kirigami film on which the spiral-curved thermal bimorphs are strategically placed. The kirigami microscanner is electrothermally transformed into an out-of-plane circular multistep pyramid by Joule heating. The circular pyramidal kirigami microscanner on a small footprint of 4.5 mm × 4.5 mm was fabricated by microelectromechanical system processes. A large four-step pyramidal actuation was successfully demonstrated, and a large 1.1-mm lens travel range at only 128 mW was achieved.

4.
Sensors (Basel) ; 20(7)2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32225086

RESUMEN

Endoscopic autofluorescence lifetime imaging is a promising technique for making quantitative and non-invasive diagnoses of abnormal tissue. However, motion artifacts caused by vibration in the direction perpendicular to the tissue surface in a body makes clinical diagnosis difficult. Thus, this paper proposes a robust autofluorescence lifetime sensing technique with a lens tracking system based on a laser beam spot analysis. Our optical setup can be easily mounted on the head of an endoscope. The variation in distance between the optical system and the target surface is tracked by the change in the spot size of the laser beam captured by the camera, and the lens actuator is feedback-controlled to suppress motion artifacts. The experimental results show that, when using a lens tracking system, the standard deviation of fluorescence lifetime is dramatically reduced. Furthermore, the validity of the proposed method is experimentally confirmed by using a bio-mimicking phantom that replicates the shape, optical parameters, and chemical component distribution of the cancerous tissue.


Asunto(s)
Técnicas Biosensibles/métodos , Diagnóstico por Imagen/métodos , Endoscopía/métodos , Imagen Óptica/métodos , Humanos , Rayos Láser , Fantasmas de Imagen
5.
Micromachines (Basel) ; 11(4)2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-32235583

RESUMEN

Large-displacement microelectromechanical system (MEMS) scanners are in high demand for a wide variety of optical applications. Kirigami, a traditional Japanese art of paper cutting and folding, is a promising engineering method for creating out-of-plane structures. This paper explores the feasibility and potential of a kirigami-inspired electrothermal MEMS scanner, which achieves large vertical displacement by out-of-plane film actuation. The proposed scanner is composed of film materials suitable for electrothermal self-reconfigurable folding and unfolding, and microscale film cuttings are strategically placed to generate large displacement. The freestanding electrothermal kirigami film with a 2 mm diameter and high fill factor is completely fabricated by careful stress control in the MEMS process. A 200 µm vertical displacement with 131 mW and a 20 Hz responsive frequency is experimentally demonstrated as a unique function of electrothermal kirigami film. The proposed design, fabrication process, and experimental test validate the proposed scanner's feasibility and potential for large-displacement scanning with a high fill factor.

6.
Int J Surg Case Rep ; 51: 400-403, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30273907

RESUMEN

INTRODUCTION: A myelolipoma is a rare benign tumor that is composed of adipose tissue and hematopoietic elements. Myelolipomas most commonly occur in the unilateral adrenal gland. Posterior mediastinal myelolipomas are extremely rare. We herein present a rare case of a multifocal myelolipoma of the mediastinum that gradually enlarged over a 12-year period after surgical resection of an adrenal myelolipoma. This is the first report of multifocal myelolipomas of the posterior mediastinum and adrenal gland. PRESENTATION OF CASE: A posterior mediastinal tumor was incidentally found by chest X-ray and computed tomography (CT) examination of a 74-year-old woman. The patient had a medical history of resection of a myelolipoma of the left adrenal gland 12 years earlier. We performed tumor extirpation under video-assisted thoracic surgery (VATS). The size of the tumor was 4.5 cm, and the postoperative diagnosis was a myelolipoma. DISCUSSION: Posterior mediastinal myelolipomas are extremely rare, and only 39 cases of mediastinal myelolipoma have been reported to date. No reports have described a multifocal myelipoma of mediastinal myelolipoma. To our knowledge, this is the first report of multifocal myelipomas of the adrenal gland and posterior mediastinum. CONCLUSION: A differential diagnosis of myelolipoma of the posterior mediastinum is important in patients with a history of myelolipoma of the adrenal gland.

7.
Opt Express ; 26(13): 16970-16983, 2018 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-30119514

RESUMEN

An optofluidic diffusion sensor using laser-induced dielectrophoresis in a device with a sputtered a-Si:H layer is presented. Diffusion sensors enabling high-speed measurement have important potential uses as bio-sensors and for quantitative analysis of nano-sized products. The present sensor was developed for measurement in a few seconds by optic observations of the sample diffusion from transient grating formed by laser-induced dielectrophoresis. As a photoconductive layer for the proposed device, we used a sputtered a-Si:H film. The optical (refractive index and extinction coefficient), structural (Raman and IR spectroscopy), and optoelectronic properties of this film, as well as its applicability to the proposed device are characterized. Nano-sized beads were measured by the fabricated device, and its performance as a diffusion sensor was validated.

8.
Sensors (Basel) ; 18(1)2018 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-29346298

RESUMEN

We propose a motion-robust laser Doppler flowmetry (LDF) system that can be used as a non-contact blood perfusion sensor for medical diagnosis. Endoscopic LDF systems are typically limited in their usefulness in clinical contexts by the need for the natural organs to be immobilized, as serious motion artifacts due to the axial surface displacement can interfere with blood perfusion measurements. In our system, the focusing lens moves to track the motion of the target using a low-frequency reference signal in the optical data, enabling the suppression of these motion artifacts in the axial direction. This paper reports feasibility tests on a prototype of this system using a microfluidic phantom as a measurement target moving in the direction of the optical axis. The frequency spectra detected and the perfusion values calculated from those spectra show that the motion tracking system is capable of suppressing motion artifacts in perfusion readings. We compared the prototype LDF system's measurements with and without motion feedback, and found that motion tracking improves the fidelity of the perfusion signal by as much as 87%.


Asunto(s)
Movimiento (Física) , Artefactos , Retroalimentación , Humanos , Flujometría por Láser-Doppler , Fantasmas de Imagen
9.
Opt Express ; 26(26): 34070-34080, 2018 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-30650836

RESUMEN

This paper proposes a novel optical hand-held viscosity sensor based on a laser-induced capillary wave method that can be used as a noncontact and quick in situ viscometry of liquid samples. Incident angle and irradiation timing control systems were integrated into the hand-held viscosity sensor to robustly measure viscosity by detecting the optical signal in a hand-held condition. We report the stability evaluation of these systems under the hand-held condition. Finally, the proposed sensor's applicability to the hand-held viscometer was confirmed by measuring the viscosity distribution that the temperature gradient of the liquid sample caused.

10.
Opt Express ; 25(2): 758-767, 2017 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-28157964

RESUMEN

This paper reports the development of an electrothermal microelectromechanical systems (MEMS) mirror with serpentine shape actuators. A micro Fresnel mirror with fringe-spacing tunability is required to realize a compact and high-speed diffusion sensor for biological samples whose diffusion coefficient changes significantly because of a conformational change. In this case, the measurement time-constant is dependent on the fringe-spacing and diffusion coefficient of the sample. In this study, a fringe-tunable MEMS mirror with an actuation voltage less than 10 V was developed. The characteristics of the fabricated mirror were investigated experimentally. A high-visibility optical interference fringe was successfully demonstrated using both an ultranarrow-linewidth solid-state laser and a low-cost compact laser diode. The experimental results demonstrated a distinct possibility of developing a measurement device using only simple and low-voltage optical components.

11.
Int J Surg Case Rep ; 41: 473-476, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29546020

RESUMEN

INTRODUCTION: Lung herniation is a rare condition defined as a protrusion of the pleural-covered lung parenchyma through an abnormal defect or weakness in the thoracic wall. Postoperative lung herniation is reported to result from a preceding operation with inadequate closure of the chest wall. PRESENTATION OF CASE: A 77-year-old woman was admitted to our hospital for treatment of hemoptysis and nausea. One year previously, she had undergone wedge resection of the right lower lobe (S6) for treatment of primary lung adenocarcinoma. Upon admission, chest radiograph and chest computed tomography showed a right lung herniation through the fifth enlarged intercostal space with right fifth and sixth rib fractures. She underwent surgical closure of the intercostal hernia using synthetic materials with fixation of the fifth and sixth ribs. The patient had developed no recurrence 9 months after surgical repair. DISCUSSION: In the present case, adequate closure of the right pleural cavity was ensured by fixation of both fifth and sixth ribs during the preceding video-assisted thoracic surgery for the primary lung carcinoma. Our patient may have had some exacerbation factors for lung herniation, increased intrathoracic pressure, attenuation of chest wall by prolonged coughing and rib fracture, and high abdominal pressure due to her hunched-over posture. CONCLUDION: It is important to know some exacerbation factors for postoperative intercostal lung herniation. Addition of monofirament-suture fixation of the ribs to patch repair is very effective for lung herniation repair in patients with concurrent lung herniation and rib fractures.

12.
Opt Express ; 23(1): 477-83, 2015 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-25835693

RESUMEN

We have developed a novel micro optical diffusion sensor (MODS) with a newly proposed comb-driven-micro Fresnel mirror (CD-MFM) scanner to detect structural changes in biological samples. By controlling the fringe spacing of the excitation laser beam, we can tune the decay time to obtain quick and precise measurements. In this study, the pre-tilted mirror is rotated by vertical comb-driven actuators; the resulting change in the mirror angle alters the fringe spacing. The validity of the proposed mirror scanner is confirmed in simulations and in an experiment using a fabricated prototype device.

13.
Sensors (Basel) ; 11(9): 8358-69, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22164080

RESUMEN

We have developed a novel nanoscale temperature-measurement method using fluorescence in the near-field called fluorescence near-field optics thermal nanoscopy (Fluor-NOTN). Fluor-NOTN enables the temperature distributions of nanoscale materials to be measured in vivo/in situ. The proposed method measures temperature by detecting the temperature dependent fluorescence lifetimes of Cd/Se quantum dots (QDs). For a high-sensitivity temperature measurement, the auto-fluorescence generated from a fiber probe should be reduced. In order to decrease the noise, we have fabricated a novel near-field optical-fiber probe by fusion-splicing a photonic crystal fiber (PCF) and a conventional single-mode fiber (SMF). The validity of the novel fiber probe was assessed experimentally by evaluating the auto-fluorescence spectra of the PCF. Due to the decrease of auto-fluorescence, a six- to ten-fold increase of S/N in the near-field fluorescence lifetime detection was achieved with the newly fabricated fusion-spliced near-field optical fiber probe. Additionally, the near-field fluorescence lifetime of the quantum dots was successfully measured by the fabricated fusion-spliced near-field optical fiber probe at room temperature, and was estimated to be 10.0 ns.


Asunto(s)
Nanotecnología , Fibras Ópticas , Puntos Cuánticos , Temperatura , Fluorescencia , Sondas Moleculares
14.
Masui ; 54(3): 298-300, 2005 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-15794110

RESUMEN

We experienced an accidental case in which 5 mg of vecuronium was administered to a 5 kg infant boy, aged 2 months, incrementally for 55 minutes during general anesthesia. He received general anesthesia at the hospital where there is no anesthesiologist. After surgery the surgeon felt an unusual situation during emergence period from general anesthesia and then noticed overdose of vecuronium. They got in touch with our department immediately and requested us to follow him up. When we reached at the bedside, we could not observe voluntary movement by him. By using neuromuscular monitoring, we could determine that a paralysis was still maintained. After a while, he started to move and breathe himself. Extubation was performed safely 4 and half hours after the final administration of vecuronium. Finally, he could recover with no adverse effect. To predict the optimal dose of a non-depolarizing muscle relaxant to a pediatric patient, routine monitoring of neuromuscular block is effective and essential.


Asunto(s)
Anestesia General , Fármacos Neuromusculares no Despolarizantes/efectos adversos , Bromuro de Vecuronio/efectos adversos , Periodo de Recuperación de la Anestesia , Sobredosis de Droga , Humanos , Lactante , Intubación Intratraqueal , Masculino
15.
Biomacromolecules ; 1(2): 149-151, 2000 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-11749146

RESUMEN

Enzymatic oxidative polymerization of m-ethynylphenol possessing two reactive groups, phenol and acetylene moieties, was carried out in aqueous methanol under air. Horseradish peroxidase and hydrogen peroxide were used as catalyst and oxidizing agent, respectively. (1)H NMR and IR analysis showed that only the phenolic moiety was polymerized to produce the polymer having the ethynyl group in the side chain. The reaction of the monomer using a copper/amine catalyst, a conventional catalyst for oxidative coupling, exclusively produced a diacetylene derivative. From these data, it was found that the peroxidase catalysis induced the chemoselective polymerization of the monomer. The resulting polymer was converted to carbonized polymer in a much higher yield than enzymatically synthesized poly(m-cresol) and is expected to have potential applications as a reactive starting polymer.

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