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1.
Eur J Neurol ; 27(6): 1003-1009, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32125747

RESUMEN

BACKGROUND AND PURPOSE: Hearing loss (HL) is one of the most influential risk factors of dementia in older adults. However, its potential association with neurodegeneration is not well established. The association between HL and cortical thickness in cognitively normal older adults was evaluated. METHODS: In all, 982 cognitively normal older adults (age ≥65 years) were identified from the Health Promotion Center at the Samsung Medical Center from September 2008 to December 2014. The participants underwent pure-tone audiometry and brain magnetic resonance imaging. HL was evaluated according to a four-frequency (0.5, 1, 2, 4 kHz) pure-tone average. Participants were divided into three groups according to pure-tone average (normal hearing ≤15 dB, minimal HL 16-25 dB, mild-to-severe HL >25 dB). Cortical thickness in the HL groups was compared with that of the normal hearing group. RESULTS: In women, right ear HL was associated with cortical thinning: the minimal HL group showed cortical thinning in the left frontal and bilateral occipital areas and the mild-to-severe HL group showed cortical thinning in the bilateral frontal, right temporal and bilateral occipital areas compared to the normal hearing group. In men, there was no significant association between HL on either side and cortical thickness. CONCLUSION: In older women, right ear HL is associated with neurodegeneration even in a cognitively normal state. Therefore, managing HL especially in older women may be an effective strategy for dementia prevention.


Asunto(s)
Adelgazamiento de la Corteza Cerebral , Pérdida Auditiva , Anciano , Audiometría de Tonos Puros , Encéfalo , Femenino , Pérdida Auditiva/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino
2.
Eur Cell Mater ; 38: 1-13, 2019 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-31332770

RESUMEN

In the current study, a method is proposed to supply culture medium into a two-layered cell-laden tubular scaffold in order to enhance cell proliferation, confluence, and viability. The two-layered cell-laden tubular scaffold was made of calcium-alginate mixed with fibroblast cells (NIH/3T3) using a lab-made double- coaxial laminar-flow generator. Afterwards, the tubular scaffold was connected to a syringe pump system using a polydimethylsiloxane (PDMS) micro-connector for long-term cell culture. Three medium pumping conditions were applied and compared: a heart-beat-mimicking pumping (20 µL/s, 1 s period, and 50 % pulse width), a continuous pumping (20 µL/s) and a non-pumping. Non-leaky connections between the tubular scaffolds and the micro-connector outlet were sustained for 13.5 ± 0.83 d in heartbeat-mimicking pumping and 11.8 ± 0.33 d in continuous pumping condition, due to the elasticity of the tubular scaffolds. Importantly, the two pumping conditions resulted in more cell proliferation, confluence, and viability than the non-pumping condition. Furthermore, analysis of newly-produced type-I collagen matrix indicated that the cells under the two pumping conditions formed a tissue-like structure. The proposed technique could further be applied to vascular co-culturing for vascular engineered tissue.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Bombas de Infusión , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Células 3T3 , Alginatos/química , Animales , Técnicas de Cultivo de Célula/instrumentación , Colágeno/metabolismo , Medios de Cultivo/química , Dimetilpolisiloxanos/química , Fibroblastos/citología , Fibroblastos/metabolismo , Fibroblastos/fisiología , Ratones , Ingeniería de Tejidos/instrumentación
3.
Transplant Proc ; 50(10): 3452-3459, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30503524

RESUMEN

BACKGROUND: One risk factor for antibody-mediated rejection (ABMR) and poor outcome after kidney transplantation is donor-specific anti‒human leukocyte antigen (anti-HLA) antibodies (DSAs). In this study we sought to determine whether the presence of DSAs that bind complement component C3d could better predict ABMR and graft loss in stable kidney transplant recipients (KTRs). METHODS: We included 220 stable KTRs in this study and screened them for DSAs from July 2013 to July 2016. RESULTS: Of the 220 KTRs, DSAs were detected in 24 (10.9%). The incidence of ABMR was 3.6% (8 of 220) overall, and C3d-DSA‒positive KTRs had a significantly higher incidence than SA-DSA‒positive KTRs (63.3% vs 38.9%, P = .03). Most C3d-binding DSAs were anti-HLA class II antibodies (11 of 13, 84.6%). Class II C3d-binding DSA was also significantly associated with graft failure on multivariate analysis, as were ABMR, chronic ABMR, and high serum creatinine. Class II C3d-binding DSA was also significantly associated with lower graft survival after ABMR. CONCLUSION: C3d-binding DSA, especially class II, was significantly associated with the risk of ABMR and graft loss in stable KTRs. We suggest that monitoring of stable KTRs for C3d-binding DSA, followed by biopsy, could aid in early recognition of ABMR and prevention of graft loss.


Asunto(s)
Complemento C3d/inmunología , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Trasplante de Riñón , Anticuerpos/inmunología , Estudios de Cohortes , Femenino , Supervivencia de Injerto/inmunología , Humanos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Donantes de Tejidos , Receptores de Trasplantes
4.
J Hand Surg Eur Vol ; 42(5): 487-492, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28490225

RESUMEN

We conducted a prospective randomized, multicentre study to compare short arm and long arm plaster casts for the treatment of stable distal radius fracture in patients older than 55 years. We randomly assigned patients over the age of 55 years who had stable distal radius fracture to either a short arm or long arm plaster cast at the first review 1 week after their injury. Radiographic and clinical follow-up was conducted at 1, 3, 5, 12 and 24 weeks following their injury. Also, degree of disability caused by each cast immobilization was evaluated at the patient's visit to remove the cast. There were no significant differences in radiological parameters between the groups except for volar tilt. Despite these differences in volar tilt, neither functional status as measured by the Disabilities of the Arm, Shoulder and Hand, nor visual analogue scale was significantly different between the groups. However, the mean score of disability caused by plaster cast immobilization and the incidence rate of shoulder pain were significantly higher in patients who had a long plaster cast. Our findings suggest that a short arm cast is as effective as a long arm cast for stable distal radius fractures in the elderly. Furthermore, it is more comfortable and introduces less restriction on daily activities. LEVEL OF EVIDENCE: II.


Asunto(s)
Moldes Quirúrgicos , Fracturas del Radio/terapia , Factores de Edad , Anciano , Femenino , Curación de Fractura , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recuperación de la Función , Resultado del Tratamiento
5.
J Nanosci Nanotechnol ; 16(2): 1988-92, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27433714

RESUMEN

The left- and right-handed helical silica nanostructures were obtained with the aid of organic templates, the formation of the nanostructures might follow a co-operation self-assembly mechanism. The chirality of the organogel self-assemblies was successfully transcribed in to the silica. The helical pitch and pore size of the silica nanotubes sensitively depended on the optical purity of the neutral gelator in the reaction mixtures.

6.
Artículo en Inglés | MEDLINE | ID: mdl-24109977

RESUMEN

This paper proposed an ultra-low power bandage-type ECG sensor (the size: 76 × 34 × 3 (mm(3)) and the power consumption: 1 mW) which allows for a continuous and real-time monitoring of a user's ECG signals over 24h during daily activities. For its compact size and lower power consumption, we designed the analog front-end, the SRP (Samsung Reconfigurable Processor) based DSP of 30 uW/MHz, and the ULP wireless RF of 1 nJ/bit. Also, to tackle motion artifacts(MA), a MA monitoring technique based on the HCP (Half-cell Potential) is proposed which resulted in the high correlation between the MA and the HCP, the correlation coefficient of 0.75 ± 0.18. To assess its feasibility and validity as a wearable health monitor, we performed the comparison of two ECG signals recorded form it and a conventional Holter device. As a result, the performance of the former is a little lower as compared with the latter, although showing no statistical significant difference (the quality of the signal: 94.3% vs 99.4%; the accuracy of arrhythmia detection: 93.7% vs 98.7%). With those results, it has been confirmed that it can be used as a wearable health monitor due to its comfortability, its long operation lifetime and the good quality of the measured ECG signal.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico por imagen , Electrocardiografía/instrumentación , Artefactos , Electricidad , Electrodos , Humanos , Monitoreo Fisiológico/instrumentación , Movimiento (Física) , Procesamiento de Señales Asistido por Computador/instrumentación , Ultrasonografía , Signos Vitales , Tecnología Inalámbrica
7.
Clin Neuropathol ; 30(6): 328-32, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22011740

RESUMEN

AIMS: The stereotactic brain biopsy is an essential diagnostic procedure in modern neurologic patient management. A side-cutting biopsy needle is one of the most widely used needle types. Recently we found a characteristic tissue artifact named "peripheral compressing artifact" in the brain tissues biopsied using a side-cutting needle of Leksell's system. We investigate prevalence, possible cause and its clinical implication of this type of artifact. MATERIALS AND METHODS: We examined the biopsies from 80 patients (44 cases of gliomas, 13 lymphomas, 7 germ cell tumors, 2 other tumors, 1 metastatic carcinoma, 4 non-tumorous conditions such as demyelinating disease and 8 non-diagnostic) in the stereotactic biopsy group with a suspected brain tumor, who underwent a stereotactic brain biopsy using side-cutting needle of Leksell's system. We also evaluated 16 cases of open brain biopsies without Leksell's system as a control group. RESULTS: The artifact is a semi-circular or band-like tissue compression in the periphery of the biopsied tissue. This artifact was found in 30 (37.5%) out of 80 cases and 57 (11.9%) out of 477 biopsied pieces. It might be produced during rotating of the inner cannula of the biopsy needle. Histologically, it might be misinterpreted as "hypercellular", "spindle", "well circumscribed", or rarely as "pseudopalisading" especially in glioma. CONCLUSIONS: Awareness of this artifact would help making the appropriate pathological diagnosis for glioma.


Asunto(s)
Artefactos , Neoplasias Encefálicas , Biopsia , Encéfalo , Glioma , Humanos , Agujas , Técnicas Estereotáxicas
8.
Anxiety Stress Coping ; 24(5): 539-60, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21516524

RESUMEN

This research examines the moderating effect of conflict avoidance on the relationship between conflict and psychological adjustment among 45 expatriate couples at two points in time. We propose a model based on the actor-partner interdependence model, which assumes both intrapersonal and interpersonal effects, to address simultaneously the effects of one's own and the other's avoidance behavior. We found substantial support for our model, especially for expatriate spouses. As expected, and only for expatriate spouses, avoidance moderated the conflict-adjustment relationship such that both one's own and one's counterpart's avoidance behavior diminished the negative effect of conflicts. Because these effects were observed only at T2 and psychological adjustment decreased from T1 to T2, our research suggests that the impact of expatriation-associated interaction particularly manifests itself in the long run.


Asunto(s)
Adaptación Psicológica , Emigrantes e Inmigrantes/psicología , Conflicto Familiar/psicología , Adulto , Femenino , Humanos , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Pruebas Psicológicas , Rol , Esposos/psicología , Encuestas y Cuestionarios , Factores de Tiempo , Adulto Joven
9.
J Biomech ; 44(5): 924-9, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21227425

RESUMEN

Achieving anatomical graft placement remains a concern in Anterior Cruciate Ligament (ACL) reconstruction. The purpose of this study was to quantify the effect of femoral graft placement on the ability of ACL reconstruction to restore normal knee kinematics under in vivo loading conditions. Two different groups of patients were studied: one in which the femoral tunnel was placed near the anterior and proximal border of the ACL (anteroproximal group, n=12) and another where the femoral tunnel was placed near the center of the ACL (anatomic group, n=10) MR imaging and biplanar fluoroscopy were used to measure in vivo kinematics in these patients during a quasi-static lunge. Patients with anteroproximal graft placement had up to 3.4mm more anterior tibial translation, 1.1mm more medial tibial translation and 3.7° more internal tibial rotation compared to the contralateral side. Patients with anatomic graft placement had motion that more closely replicated that of the intact knee, with anterior tibial translation within 0.8mm, medial tibial translation within 0.5mm, and internal tibial rotation within 1°. Grafts placed anteroproximally on the femur likely provide insufficient restraint to these motions due to a more vertical orientation. Anatomical femoral placement of the graft is more likely to reproduce normal ACL orientation, resulting in a more stable knee. Therefore, achieving anatomical graft placement on the femur is crucial to restoring normal knee function and may decrease the rates of joint degeneration after ACL reconstruction.


Asunto(s)
Ligamento Cruzado Anterior/cirugía , Fémur/cirugía , Articulación de la Rodilla/patología , Adulto , Ligamento Cruzado Anterior/fisiopatología , Fenómenos Biomecánicos , Femenino , Fémur/patología , Fluoroscopía/métodos , Humanos , Rodilla/fisiología , Rodilla/fisiopatología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Movimiento (Física) , Procedimientos de Cirugía Plástica/métodos , Tibia/fisiopatología
10.
Environ Technol ; 29(11): 1191-8, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18975851

RESUMEN

A digital processing method is described for determining the size spectra of sub-micron particles in natural water from transmission electron microscopy images of particles collected by ultracentrifugation, and is compared with traditional manual counting and size measurement methods. The processing method is based on the use of the MatLab Image Processing toolbox. The manual method was found to underestimate the population of particles smaller than 40 nm equivalent radius, primarily because of a "fatigue factor" in counting the very large numbers of particles in this size range. By contrast, the manual method produced higher particle counts of particles >50 nm radius, primarily because manual counters tend to group together particles as aggregates that digital processing indicates are not contiguous. The digitally-produced size spectrum for a river water sample was found to closely follow a power-series law down to the smallest particle size.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Tamaño de la Partícula , Agua/análisis , Microscopía Electrónica de Transmisión , Reproducibilidad de los Resultados , Ultracentrifugación
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