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Rapid eye movement sleep is associated with distinct changes in various biomedical signals that can be easily captured during sleep, lending themselves to automated sleep staging using machine learning systems. Here, we provide a perspective on the critical characteristics of biomedical signals associated with rapid eye movement sleep and how they can be exploited for automated sleep assessment. We summarise key historical developments in automated sleep staging systems, having now achieved classification accuracy on par with human expert scorers and their role in the clinical setting. We also discuss rapid eye movement sleep assessment with consumer sleep trackers and its potential for unprecedented sleep assessment on a global scale. We conclude by providing a future outlook of computerised rapid eye movement sleep assessment and the role AI systems may play.
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We investigate a novel distributed Brillouin optical time domain reflectometer (BOTDR) using standard telecommunication fibers based on single-photon avalanche diodes (SPADs) in gated mode, ν -BOTDR, with a range of 120 km and 10 m spatial resolution. We experimentally demonstrate the ability to perform a distributed temperature measurement, by detecting a hot spot at 100 km. Instead of using a frequency scan like conventional BOTDR, we use a frequency discriminator based on the slope of a fiber Bragg grating (FBG) to convert the count rate of the SPAD into a frequency shift. A procedure to take into account the FBG drift during the acquisition and perform sensitive and reliable distributed measurements is described. We also present the possibility to differentiate strain and temperature.
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Angular momentum is an important physical property that plays a key role in light-matter interactions, such as spin-orbit interaction. Here, we investigate theoretically and experimentally the spin-orbit interaction between a circularly polarized optical (spin) and a transverse vortex acoustic wave (orbital) using Brillouin backscattering in a silica optical nanofiber. We specifically explore the state of polarization of Brillouin backscattering induced by the TR21 torso-radial vortex acoustic mode that carries an orbital angular momentum. Using a full-vectorial theoretical model, we predict and observe two operating regimes for which the backscattered Brillouin signal is either depolarized or circularly polarized, depending on the input pump polarization. We demonstrate that when the pump is circularly polarized and thus carries a spin angular momentum, the backscattered signal undergoes a handedness reversal of circular polarization due to opto-acoustic spin-orbit interaction and the conservation of overall angular momentum.
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Piezoelectric stretching of optical fiber is a technique that enables the creation of optical delays of a few picoseconds; this is useful in a variety of applications in interferometry or optical cavities. Most commercial fiber stretchers involve lengths of fiber of a few tens of meters. Using a 120-mm-long optical micro-nanofiber, we can create a compact optical delay line that achieves tunable delays of up to 19 ps at telecommunication wavelengths. The high elasticity of silica and the micron-scale diameter allow this significant optical delay to be achieved with low tensile force while keeping the overall length short. We successfully report both static and dynamic operation of this novel, to the best of our knowledge, device. It could find application in interferometry and laser cavity stabilization, where short optical paths and strong resistance to the environment would be required.
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Nanofibras , Macas , Desenho de Equipamento , Lasers , Fibras ÓpticasRESUMO
Cantú syndrome (CS) is an extremely rare autosomal dominant hereditary disease characterized by congenital hypertrichosis, distinct coarse facial features, cardiac defects, and other abnormalities in the skeletal and neurological systems. At present, cases with pathognomonic clinical manifestations are increasingly confirmed by genetic analysis. Two causative genes for CS are the well-known ABCC9 and the more rarely reported KCNJ8. Here, we report three Vietnamese children with CS, confirmed through genetic testing, presenting de novo ABCC9 mutations. The patients shared some common clinical manifestations, including congenital hypertrichosis, distinctive facial features, and a history of polyhydramnios during pregnancy. Concerning the various cardiac and neurological problems in the lifetime of patients with CS, an accurate diagnosis and appropriate management, especially genetic counseling, should be clinically applied in CS. Thus, our findings might modestly contribute to the global CS data, providing practical insights into CS manifestations.
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Hipertricose , Osteocondrodisplasias , Cardiomegalia/genética , Criança , Humanos , Hipertricose/diagnóstico , Hipertricose/genética , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , VietnãRESUMO
Generalized erythrodermic psoriasis (GEP) is a rare and potentially life-threatening variant of psoriasis. Possible triggers that have been identified to date include poorly controlled psoriasis, medications, abrupt discontinuation of anti-psoriatic treatment, and underlying systemic illnesses. However, vaccines have rarely been reported to exacerbate GEP. Herein, we report two unique cases with GEP exacerbated following a dose of the BNT162b2 mRNA vaccine for COVID-19 (as their second dose, the first being the mRNA-1273 vaccine). Based on our observations and a literature review, vaccination was considered the most likely trigger of GEP due to the close temporal relationship between the second vaccination and the onset of GEP.
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Vacina BNT162 , COVID-19 , Psoríase , Vacina de mRNA-1273 contra 2019-nCoV , Vacina BNT162/efeitos adversos , COVID-19/prevenção & controle , Humanos , Psoríase/induzido quimicamente , SARS-CoV-2 , Vacinação/efeitos adversosRESUMO
Along the pathway from behavioral symptoms to the development of psychotic disorders sits the multivariate mediating brain. The functional organization and structural topography of large-scale multivariate neural mediators among patients with brain disorders, however, are not well understood. Here, we design a high-dimensional brain-wide functional mediation framework to investigate brain regions that intermediate between baseline behavioral symptoms and future conversion to full psychosis among individuals at clinical high risk (CHR). Using resting-state functional magnetic resonance imaging (fMRI) data from 263 CHR subjects, we extract an α brain atlas and a ß brain atlas: the former underlines brain areas associated with prodromal symptoms and the latter highlights brain areas associated with disease onset. In parallel, we identify and separate mediators that potentially positively and negatively mediate symptoms and psychosis, respectively, and quantify the effect of each neural mediator on disease development. Taken together, these results paint a brain-wide picture of neural markers that are potentially mediating behavioral symptoms and the development of psychotic disorders; additionally, they underscore a statistical framework that is useful to uncover large-scale intermediating variables in a regulatory biological system.
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Sintomas Comportamentais/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Sintomas Prodrômicos , Transtornos Psicóticos/diagnóstico por imagem , Sintomas Comportamentais/fisiopatologia , Mapeamento Encefálico/métodos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Análise de Mediação , Transtornos Psicóticos/fisiopatologia , Adulto JovemRESUMO
The evolution of the light intensity along an optical waveguide is evaluated by analysing far-field right-angle Rayleigh light scattering. The method is based on point by point spectral mapping distributed along the optical waveguide with a micrometric spatial resolution given by a confocal microscope, a high spectral resolution given by a spectrometer, and a high signal-to-noise ratio given by a highly cooled detector. This non-destructive and non-invasive experimental method allows the observation of the general Rayleigh scattering profile of the optical waveguide in a nominal operation, i.e., whatever the power or the wavelength of the light source, and can be applied to micrometer-scale waveguides of several centimeters in length, for which the longitudinal characterization is challenging. Applied to a tapered optical fiber, called nanofiber, with submicrometer final diameter and several centimeters long, the method has proved its capacity to collect different optical characteristics such as optical losses, mode beatings, transition from core-cladding to cladding-air guidance for different modes, localization of punctual defects, leaking of high order modes no longer guided by the fiber. Furthermore, the experimental results are successfully compared to measurements provided by the state-of-the-art Optical Backscatter Reflectometer system, and to numerical simulations. Moreover, coupled to the spectral resolution of the spectrometer, the method have allowed the distributed measurements of the Raman cascading process along the nanofiber, for the first time to our knowledge. The experimental technique developed in this work is complementary to other characterization methods generally focused on the optical parameters of the waveguide input or output. This technique can also be extended to others waveguides whatever its geometry which represents a strong interest for deepen optical characterization of photonics waveguides, or for other optical regimes characterized by spectral evolution of the field propagating along the waveguide.
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BACKGROUND AND OBJECTIVES: To investigate the safety and efficacy of a dual-wavelength 1064/532-nm picosecond-domain laser for tattoo removal in Vietnamese patients. STUDY DESIGN/MATERIALS AND METHODS: This prospective clinical study enrolled 30 subjects with 52 decorative tattoos treated with up to six treatments of laser removal at intervals of 6-8 weeks. Safety and efficacy were assessed at each treatment session and at 4 weeks after the final session. A "good" response was defined as at least 75% clearance of tattoo pigments. RESULTS: A significant reduction of tattoo appearance was achieved in all subjects. 88.5% of tattoos exhibited a "good" response to treatment by the end of the six sessions and more than 36% of tattoos exhibited better than "good" responses. Adverse events were common in the early period after treatment but did not persist in most patients. Only one case of prolonged hypopigmentation was reported. CONCLUSIONS: Treatment using a 1064/532-nm picosecond laser is an effective approach for removal of decorative tattoos, which poses a minimal risk of long-term adverse events in patients with Fitzpatrick skin type III or IV. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.
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Albinismo Oculocutâneo , Lasers de Estado Sólido , Procedimentos de Cirurgia Plástica , Tatuagem , Humanos , Lasers de Estado Sólido/uso terapêutico , Estudos ProspectivosRESUMO
Twelve new azole compounds were synthesized through an ene reaction involving methylidene heterocycles and phenylmaleimide, producing four oxazoles, five thiazoles, and one pyridine derivative, and ethyl glyoxal for an oxazole and a thiazole compound. The twelve azoles have a stereogenic center in their structure. Hence, a method to separate the enantiomeric pairs, must be provided if any further study of chemical and pharmacological importance of these compounds is to be accomplished. Six chiral stationary phases were assayed: four were based on macrocyclic glycopeptide selectors and two on linear carbohydrates, i.e., derivatized maltodextrin and amylose. The enantiomers of the entire set of new chiral azole compounds were separated using the three different mobile phase elution modes: normal phase, polar organic, and reversed phase. The most effective chiral stationary phase was the MaltoShell column, which was able to separate ten of the twelve compounds in one elution mode or another. Structural similarities in the newly synthesized oxazoles provided some insights into possible chiral recognition mechanisms.
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Amilose/química , Azóis/química , Azóis/isolamento & purificação , Glicopeptídeos/química , Polissacarídeos/química , Estrutura Molecular , EstereoisomerismoRESUMO
Due to its subtropical origins, rice (Oryza sativa) is sensitive to low-temperature stress. In this study, we identify LOC_Os04g24110, annotated to encode the UDP-glycosyltransferase enzyme UGT90A1, as a gene associated with the low-temperature seedling survivability (LTSS) quantitative trait locus qLTSS4-1. Differences between haplotypes in the control region of OsUGT90A1 correlate with chilling tolerance phenotypes, and reflect differential expression between tolerant and sensitive accessions rather than differences in protein sequences. Expression of OsUGT90A1 is initially enhanced by low temperature, and its overexpression helps to maintain membrane integrity during cold stress and promotes leaf growth during stress recovery, which are correlated with reduced levels of reactive oxygen species due to increased activities of antioxidant enzymes. In addition, overexpression of OsUGT90A1 in Arabidopsis improves freezing survival and tolerance to salt stress, again correlated with enhanced activities of antioxidant enzymes. Overexpression of OsUGT90A1 in rice decreases root lengths in 3-week-old seedlings while gene-knockout increases the length, indicating that its differential expression may affect phytohormone activities. We conclude that higher OsUGT90A1 expression in chilling-tolerant accessions helps to maintain cell membrane integrity as an abiotic stress-tolerance mechanism that prepares plants for the resumption of growth and development during subsequent stress recovery.
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Oryza , Membrana Celular , Temperatura Baixa , Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Glicosiltransferases/genética , Oryza/genética , Plântula/genéticaRESUMO
In our search for new small molecules activating procaspase-3, we have designed and synthesized a series of new acetohydrazides incorporating both 2-oxoindoline and 4-oxoquinazoline scaffolds. Biological evaluation showed that a number of these acetohydrazides were comparably or even more cytotoxic against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer) in comparison to PAC-1, a first procaspase-3 activating compound, which was used as a positive control. One of those new compounds, 2-(6-chloro-4-oxoquinazolin-3(4H)-yl)-N'-[(3Z)-5-methyl-2-oxo-1,2-dihydro-3H-indol-3-ylidene]acetohydrazide activated the caspase-3 activity in U937 human lymphoma cells by 5-fold higher than the untreated control. Three of the new compounds significantly induced necrosis and apoptosis in U937 cells.
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Antineoplásicos/farmacologia , Caspase 3/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Hidrazinas/farmacologia , Oxindóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores de Cisteína Proteinase/síntese química , Inibidores de Cisteína Proteinase/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrazinas/síntese química , Hidrazinas/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxindóis/química , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
Optical nanofibers have recently emerged as attractive nanophotonic platforms for many applications ranging from quantum technologies to nonlinear optics, due to both their tight optical confinement and their wide evanescent field. Herein we examine theoretically the optical Kerr effect induced by the evanescent field of a silica nanofiber surrounded by different nonlinear liquids such as water, ethanol and acetone and we further compare them with air cladding. Our results show that the evanescent Kerr effect significantly dominates the usual Kerr effect inside the silica core for sub-wavelength diameters below 560 nm, using acetone. We further report the observation of the evanescent Kerr effect through surrogate measurements of stimulated Raman-Kerr scattering (SRKS) in an acetone-immersed silica nanofiber. Our findings open the way towards potential applications of optical nanofibers to ultra-sensitive liquid sensing or to enhancing the nonlinear effects through the evanescent field.
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In search for novel small molecules with antitumor cytotoxicity via activating procaspase-3, we have designed and synthesized three series of novel (E)-N'-benzylidene-4-oxoquinazolin-3(4H)-yl)acetohydrazides (5a-j, 6a-h, and 7a-h). On the phenyl ring ò the benzylidene part, three different substituents, including 2-OH-4-OCH3, 4-OCH3, and 4-N(CH3)2, were introduced, respectively. Biological evaluation showed that the acetohydrazides in series 5a-j, in which the phenyl ring of the benzylidene part was substituted by 2-OH-4-OCH3 substituent, exhibited potent cytotoxicity against three human cancer cell lines (SW620, colon; PC-3, prostate; NCI-H23, lung). Most of the compounds, in this series, especially compounds 5c, 5b and 5h, also significantly activated caspase-3 activity. Among these, compound 5c displayed 1.61-fold more potent than PAC-1 as caspase-3 activator. Cell cycle analysis showed that compounds 5b, 5c, and 5h significantly arrested the cell cycle in G1 phase. Further apoptotic studies also demonstrated compounds 5b, 5c, and 5h as strong apoptotic cell death inducers. The docking simulation studies showed that these compounds could activate procaspase via chelating Zn2+ ion bound to the allosteric site of the zymogen.
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Antineoplásicos/síntese química , Caspases/metabolismo , Hidrazinas/síntese química , Quinazolinas/química , Sítio Alostérico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrazinas/farmacologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Transdução de Sinais , Relação Estrutura-AtividadeRESUMO
We present a Raman converter emitting at 583 nm on the second Stokes order of a line of propan-2-ol pumped by a microlaser at 532 nm in the sub-nanosecond regime. We used a mixture of liquids to adapt the transmission band of a photonic bandgap fiber. The internal conversion efficiency is 67% in photon numbers, and the output power is 1.06 mW, corresponding to a maximum peak power of 338 W. The beam delivered by the converter presents a Gaussian spatial structure and a high spectral brightness, typically more than five times higher than supercontinuum sources in this spectral range.
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The theoretical tenets of academic engagement, as outlined by Schaufeli and colleagues, have received limited attention. There is credence to indicate that Schaufeli et al.'s conceptualization has educational implications. Extending this avenue of inquiry, we report two longitudinal studies that explore the motivation-related attributes of engagement within the framework of self-efficacy. A number of research questions were developed for examination-for example, does enactive learning experience influence academic achievement, via students' engrossment (i.e. absorption) of a subject matter? Does students' sense of resilience and persistence (i.e. vigor) heighten their self-efficacy beliefs for academic learning? For the two studies (Study 1: 311 Year 11 students; Study 2: 249 Year 12 students), utilizing different cohorts, we measured these constructs at multiple time points. Existing Likert-scale inventories were administered repeatedly, and data collected were analysed using causal modeling procedures. MPlus 7.2 yielded a number of key findings-for example: (a) the positive impact of Time 1 enactive learning experience on Time 2 absorption and vigor, (b) the positive impact of Time absorption on Time 3 self-efficacy, (c) the positive impact of Time 2 absorption on Time 4 achievement and (d) the positive impact of Time 1 self-efficacy on Time 2 absorption and vigor.
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Aprendizagem , Motivação , Autoeficácia , Estudantes/psicologia , Logro , Adolescente , Atenção , Feminino , Humanos , Estudos Longitudinais , Masculino , Inventário de Personalidade , Resiliência PsicológicaRESUMO
Arabidopsis thaliana MYB80 (formerly MYB103) is expressed in the tapetum and microspores between anther developmental stages 6 and 10. MYB80 encodes a MYB transcription factor that is essential for tapetal and pollen development. Using microarray analysis of anther mRNA, we identified 404 genes differentially expressed in the myb80 mutant. Employing the glucocorticoid receptor system, the expression of 79 genes was changed when MYB80 function was restored in the myb80 mutant following induction by dexamethasone. Thirty-two genes were analyzed using chromatin immunoprecipitation, and three were identified as direct targets of MYB80. The genes encode a glyoxal oxidase (GLOX1), a pectin methylesterase (VANGUARD1), and an A1 aspartic protease (UNDEAD). All three genes are expressed in the tapetum and microspores. Electrophoretic mobility shift assays confirmed that MYB80 binds to all three target promoters, with the preferential binding site containing the CCAACC motif. TUNEL assays showed that when UNDEAD expression was silenced using small interfering RNA, premature tapetal and pollen programmed cell death occurred, resembling the myb80 mutant phenotype. UNDEAD possesses a mitochondrial targeting signal and may hydrolyze an apoptosis-inducing protein(s) in mitochondria. The timing of tapetal programmed cell death is critical for pollen development, and the MYB80/UNDEAD system may regulate that timing.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/anatomia & histologia , Arabidopsis/crescimento & desenvolvimento , Flores/citologia , Flores/fisiologia , Pólen/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Sequência de Bases , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Morte Celular/fisiologia , Imunoprecipitação da Cromatina , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Análise em Microsséries , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Pólen/citologia , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição/genéticaRESUMO
A W/ZSM-5 zeolite was successfully prepared by incorporating tungsten transition metal into a zeolite structure using a conventional impregnation method. The as-obtained W/ZSM-5 zeolite was characterized using several characterization techniques such as XRD, IR and SEM-EDS. The catalyst was then applied to a cascade, single-batch reaction to synthesize bio-polyol from sunflower oils using H2O2 in isopropanol solvent. The obtained results indicated that the W/ZSM-5 zeolite had high catalytic efficiency in the epoxidation of the double bond of vegetable oil and the epoxy ring opening reaction to form bio-polyol. The effect of different reaction conditions on bio-polyol synthesis, such as the dosage of the catalyst and reaction time, were investigated. Bio-polyol was obtained from sunflower oil with a hydroxyl number of 160 mg KOH per g and functionality of 2.9 OH groups per mol. The as-synthesized sunflower oil-based polyol was used to replace fossil-based polyol in the fabrication of a bio-polyurethane-based composite with high oil uptake capacity. The oil adsorption capacity of the porous polyurethane-corn stalk composite was relatively high, up to 15.07 g g-1. In comparison with neat polyurethane and lignocellulosic materials, the new porous bio-composite had higher oil uptake capacity.
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Sleep abnormalities can have severe health consequences. Automated sleep staging, i.e. labelling the sequence of sleep stages from the patient's physiological recordings, could simplify the diagnostic process. Previous work on automated sleep staging has achieved great results, mainly relying on the EEG signal. However, often multiple sources of information are available beyond EEG. This can be particularly beneficial when the EEG recordings are noisy or even missing completely. In this paper, we propose CoRe-Sleep, a Coordinated Representation multimodal fusion network that is particularly focused on improving the robustness of signal analysis on imperfect data. We demonstrate how appropriately handling multimodal information can be the key to achieving such robustness. CoRe-Sleep tolerates noisy or missing modalities segments, allowing training on incomplete data. Additionally, it shows state-of-the-art performance when testing on both multimodal and unimodal data using a single model on SHHS-1, the largest publicly available study that includes sleep stage labels. The results indicate that training the model on multimodal data does positively influence performance when tested on unimodal data. This work aims at bridging the gap between automated analysis tools and their clinical utility.
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Eletroencefalografia , Sono , Humanos , Fatores de Tempo , Eletroencefalografia/métodos , Fases do Sono/fisiologiaRESUMO
Multiple complicated concurrent hernias with obturator hernia and paraesophageal hernia unusually occur in clinical settings. The obturator hernias belong to a rare pelvic hernia that accounts for a minority of all abdominal hernias. Besides, paraesophageal hernias occur commonly in elderly female patients. Clinical manifestations of these hernias are usually unspecific and the diagnosis is based on computed tomography (CT). In this paper, we presented a case of multiple complicated hernias in an 81-year-old woman. She was admitted to our hospital due to intestinal obstruction that was caused by a simultaneous obturator and paraesophageal hernia. She was successfully treated by laparoscopic hernia repair. Postoperative progression was favorable. She was then discharged from the hospital after four hospital days.