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1.
Small ; 20(24): e2307200, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38197540

RESUMEN

Uniform lithium deposition is essential to hinder dendritic growth. Achieving this demands even seed material distribution across the electrode, posing challenges in correlating the electrode's surface structure with the uniformity of seed material distribution. In this study, the effect of periodic surface and facet orientation on seed distribution is investigated using a model system consisting of a wrinkled copper (Cu)/graphene structure with a [100] facet orientation. A new methodology is developed for uniformly distributed silver (Ag) nanoparticles over a large area by controlling the surface features of Cu substrates. The regularly arranged Ag nanoparticles, with a diameter of 26.4 nm, are fabricated by controlling the Cu surface condition as [100]-oriented wrinkled Cu. The wrinkled Cu guides a deposition site for spherical Ag nanoparticles, the [100] facet determines the Ag morphology, and the presence of graphene leads to spacings of Ag seeds. This patterned surface and high lithiophilicity, with homogeneously distributed Ag nanoparticles, lead to uniform Li+ flux and reduced nucleation energy barrier, resulting in excellent battery performance. The electrochemical measurements exhibit improved cyclic stability over 260 cycles at 0.5 mA cm-2 and 100 cycles at 1.0 mA cm-2 and enhanced kinetics even under a high current density of 5.0 mA cm-2.

2.
Tech Coloproctol ; 27(7): 589-599, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36971849

RESUMEN

PURPOSE: The da Vinci SP® (dVSP) surgical system (Intuitive Surgical, Sunnyvale, CA, USA), a robotic platform designed for single-incision surgery, overcame the need for multiple ports in traditional robotic surgery and issues including triangulation and retraction in single-incision laparoscopic surgery. However, previous studies only included case reports or series with small sample sizes. The aim of this study was to assess the safety and performance of the dVSP surgical system and its instruments and accessories for colorectal procedures. METHODS: The medical records of patients who had surgery with the dVSP from March 2019 to September 2021 at Ewha Womans University Seoul Hospital were investigated. The pathologic and follow-up data of patients who had malignant tumors were analyzed separately to evaluate oncological safety. RESULTS: Fifty patients (26 male and 24 female) with a median age of 59 years (interquartile range 52.5-63.0 years) were enrolled. The procedures included low anterior resection with total mesorectal excision (n = 16), sigmoid colectomy with complete mesocolic excision and central vessel ligation (CME + CVL) (n = 14), right colectomy with CME + CVL (n = 9), left colectomy with CME + CVL (n = 4), right colectomy (n = 6), and sigmoid colectomy (n = 1). Operative time significantly decreased after 25 cases (early phase vs. late phase; operative time 295.0 min vs. 250.0 min, p = 0.015; docking time 16.0 min vs. 12.0 min, p = 0.001; console time 212.0 min vs. 190.0 min, p = 0.019). Planned procedures were successfully completed in all patients. Postoperative outcomes were acceptable with only six cases of mild adverse events through a 3-month follow-up. No local recurrence and only one case of systemic recurrence occurred within 1 year postoperatively. CONCLUSIONS: This study demonstrated the surgical and oncological safety and feasibility of dVSP, which may be a novel surgical platform for colorectal surgery.


Asunto(s)
Cirugía Colorrectal , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Robótica , Humanos , Masculino , Femenino , Persona de Mediana Edad , Procedimientos Quirúrgicos Robotizados/métodos , Robótica/métodos , Colectomía/métodos , Tempo Operativo , Estudios Retrospectivos
3.
Nano Lett ; 22(2): 761-767, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35029396

RESUMEN

Electric vehicle manufacturers worldwide are demanding superior lithium-ion batteries, with high energy and power densities, compared to gasoline engines. Although conversion-type metal oxides are promising candidates for high-capacity anodes, low initial Coulombic efficiency (ICE) and poor capacity retention have hindered research on their applications. In this study, the ICE of conversion-type MoO3 is investigated, with a particular focus on the delithiation failure. A computational modeling predicts the concentration gradient of Li+ in MoO3 particles. The highly delithiated outer region of the particle forms a layer with low electronic conductivity, which impedes further delithiation. A comparative study using various sizes of MoO3 particles demonstrated that the electrode failure during delithiation is governed by the concentration gradient and the subsequent formation of a resistive shell. The proposed failure mechanism provides critical guidance for the development of conversion-type anode materials with improved electrochemical reversibility.

4.
J Synchrotron Radiat ; 29(Pt 1): 111-117, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34985428

RESUMEN

A novel scheme to measure the longitudinal emittance and phase space profile in an electron storage ring by using correlations between time and the vertical coordinate, and between energy and the horizontal coordinate, is proposed. This longitudinal profile measurement scheme will help to demonstrate recent results of advanced studies for manipulating the longitudinal beam profile and for investigating beam instability in an electron storage ring.

5.
J Synchrotron Radiat ; 27(Pt 6): 1510-1517, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33147176

RESUMEN

An investigation of the damping wiggler effect to reduce the emittance in the Pohang Accelerator Laboratory (PAL), a fourth-generation storage ring (4GSR) that uses a multi-bend achromat, is presented. A 4GSR lattice which has reduced emittance and increased dynamic aperture to amplify the synergy with two existing light sources (PLS-II and PAL-XFEL) at PAL is described.

6.
J Synchrotron Radiat ; 27(Pt 4): 864-869, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33565994

RESUMEN

This paper presents the required structure and function of a ring-FEL as a radiation source for extreme ultraviolet radiation lithography (EUVL). A 100 m-long straight section that conducts an extremely low emittance beam from a fourth-generation storage ring can increase the average power at 13.5 nm wavelength to up to 1 kW without degrading the beam in the rest of the ring. Here, simulation results for a ring-FEL as a EUVL source are described.

7.
J Eur Acad Dermatol Venereol ; 34(8): 1842-1850, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31919901

RESUMEN

BACKGROUND: Several studies have achieved high-level performance of melanoma detection using convolutional neural networks (CNNs). However, few have described the extent to which the implementation of CNNs improves the diagnostic performance of the physicians. OBJECTIVE: This study is aimed at developing a CNN for detecting acral lentiginous melanoma (ALM) and investigating whether its implementation can improve the initial decision for ALM detection made by the physicians. METHODS: A CNN was trained using 1072 dermoscopic images of acral benign nevi, ALM and intermediate tumours. To investigate whether the implementation of CNN can improve the initial decision for ALM detection, 60 physicians completed a three-stage survey. In Stage I, they were asked for their decisions solely on the basis of dermoscopic images provided to them. In Stage II, they were also provided with clinical information. In Stage III, they were provided with the additional diagnosis and probability predicted by the CNN. RESULTS: The accuracy of ALM detection in the participants was 74.7% (95% confidence interval [CI], 72.6-76.8%) in Stage I and 79.0% (95% CI, 76.7-81.2%) in Stage II. In Stage III, it was 86.9% (95% CI, 85.3-88.4%), which exceeds the accuracy delivered in Stage I by 12.2%p (95% CI, 10.1-14.3%p) and Stage II by 7.9%p (95% CI, 6.0-9.9%p). Moreover, the concordance between the participants considerably increased (Fleiss-κ of 0.436 [95% CI, 0.437-0.573] in Stage I, 0.506 [95% CI, 0.621-0.749] in Stage II and 0.684 [95% CI, 0.621-0.749] in Stage III). CONCLUSIONS: Augmented decision-making improved the performance of and concordance between the clinical decisions of a diverse group of experts. This study demonstrates the potential use of CNNs as an adjoining, decision-supporting system for physicians' decisions.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Dermoscopía , Humanos , Melanoma/diagnóstico por imagen , Redes Neurales de la Computación , Neoplasias Cutáneas/diagnóstico por imagen
8.
Skin Res Technol ; 24(1): 80-84, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28722291

RESUMEN

BACKGROUND/PURPOSE: Focus on the hair and hair cuticle is increasing. The hair cuticle is the first layer to be exposed to damage and the area of primary protection. For such reasons, hair product manufacturers consider cuticle protection important. However, previous studies used only visual assessment to examine the cuticle. This study aimed to obtain the changes in cuticles and measure hair roughness using a HIROX microscope. METHODS: A total of 23 female subjects used the same products daily for 4 weeks. Three hair samples per subject were collected from three different areas of the head. Measurements were taken before and after 4 weeks of daily product use. RESULTS: The hair surface changes were clearly observed on the captured images. Moreover, hair surface roughness was observed using various parameters on HIROX software. After 4 weeks of daily product use, the roughness parameter value of the hair surface was significantly decreased. CONCLUSION: Our result suggests that the hair roughness analytical method using HIROX can be a new paradigm for high-quality quantitative analysis of the hair cuticle.


Asunto(s)
Preparaciones para el Cabello/farmacología , Cabello/efectos de los fármacos , Procesamiento de Imagen Asistido por Computador/métodos , Adulto , Comportamiento del Consumidor , Femenino , Cabello/patología , Humanos , Microscopía/métodos , Persona de Mediana Edad , Programas Informáticos , Propiedades de Superficie/efectos de los fármacos
9.
Skin Res Technol ; 24(1): 117-122, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28718523

RESUMEN

BACKGROUND: Although measuring would size using digital photography is a quick and simple method to evaluate the skin wound, the possible compatibility of it has not been fully validated. PURPOSE: To investigate the error rate of our newly developed wound surface area calculation using digital photography. METHODS: Using a smartphone and a digital single lens reflex (DSLR) camera, four photographs of various sized wounds (diameter: 0.5-3.5 cm) were taken from the facial skin model in company with color patches. The quantitative values of wound areas were automatically calculated. The relative error (RE) of this method with regard to wound sizes and types of camera was analyzed. RESULTS: RE of individual calculated area was from 0.0329% (DSLR, diameter 1.0 cm) to 23.7166% (smartphone, diameter 2.0 cm). In spite of the correction of lens curvature, smartphone has significantly higher error rate than DSLR camera (3.9431±2.9772 vs 8.1303±4.8236). However, in cases of wound diameter below than 3 cm, REs of average values of four photographs were below than 5%. In addition, there was no difference in the average value of wound area taken by smartphone and DSLR camera in those cases. CONCLUSION: For the follow-up of small skin defect (diameter: <3 cm), our newly developed automated wound area calculation method is able to be applied to the plenty of photographs, and the average values of them are a relatively useful index of wound healing with acceptable error rate.


Asunto(s)
Traumatismos Faciales/patología , Fotograbar/métodos , Piel/lesiones , Algoritmos , Traumatismos Faciales/fisiopatología , Humanos , Fotograbar/instrumentación , Piel/patología , Teléfono Inteligente , Cicatrización de Heridas
10.
J Eur Acad Dermatol Venereol ; 32(12): 2171-2177, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30067886

RESUMEN

BACKGROUND: Due to the propensity for local recurrence, Mohs micrographic surgery (MMS) has been suggested for the treatment of dermatofibrosarcoma protuberans (DFSP) and it has shown improved clinical outcomes. Recently, some authors suggested that MMS using paraffin-embedded sections (paraffin MMS) is superior in DFSP treatment compared with the conventional frozen MMS method. However, there have been no studies comparing frozen and paraffin MMS for the treatment of DFSP. OBJECTIVES: To compare the outcomes between DFSP patients who underwent frozen MMS and paraffin MMS. METHODS: Seventy-one DFSP patients treated with frozen MMS (n = 30) or paraffin MMS (n = 41) from 2003 to 2017 at a single institution were retrospectively reviewed. Recurrence rate and recurrence-free survival between frozen and paraffin MMS were assessed. RESULTS: During the mean follow-up duration of 25.4 months, four patients (frozen MMS, n = 1; and paraffin MMS, n = 3) showed recurrence after MMS. Although the local recurrence rate of the frozen MMS group (3.3%) was lower than that of the paraffin MMS group (7.3%), the difference was not statistically significant. In addition, recurrence-free survival was not significantly different between the two groups (P = 0.168). CONCLUSIONS: Frozen MMS, which has the advantages of shorter surgery time and immediate closure, is as effective as paraffin MMS in the treatment of DFSP.


Asunto(s)
Dermatofibrosarcoma/cirugía , Secciones por Congelación , Cirugía de Mohs , Recurrencia Local de Neoplasia/patología , Adhesión en Parafina , Neoplasias Cutáneas/cirugía , Adolescente , Adulto , Anciano , Niño , Preescolar , Dermatofibrosarcoma/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios Retrospectivos , Neoplasias Cutáneas/patología , Adulto Joven
11.
Am J Transplant ; 17(2): 365-376, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27376767

RESUMEN

We investigated whether serum deprivation induces islet amyloid polypeptide (IAPP) oligomer accumulation and/or a proinflammatory response and, if so, whether the addition of interleukin (IL)-1 receptor antagonist to the culture medium can relieve the proinflammatory response during serum-deprived culture of nonhuman primate (NHP) islets. After culture in medium with and without Ana under serum-deprived culture conditions, IAPP oligomer/amyloid accumulation, in vitro viability, islet function, cytokine secretion, and posttransplantation outcome in streptozotocin-induced diabetic nude mice were determined in islets isolated from heterozygote human IAPP transgenic (hIAPP+/- ) mice and/or NHP islets. Serum deprivation induced accumulation of IAPP oligomer, but not amyloid, in NHP islets. Anakinra (Ana) protected islets from the serum deprivation-induced impairment of in vitro viability and glucose-stimulated insulin secretion and attenuated serum deprivation-induced caspase-1 activation, transcription, and secretion of IL-1ß, IL-6, and tumor necrosis factor-α in hIAPP+/- mice and NHP islets. Supplementation of medium with Ana during serum-deprived culture also improved posttransplantation in vivo outcomes of NHP islets. In conclusion, serum deprivation induced accumulation of IAPP oligomers and proinflammatory responses in cultured isolated islets. Supplementation of the culture medium with Ana attenuated the functional impairment and proinflammatory responses induced by serum deprivation in ex vivo culture of NHP islets.


Asunto(s)
Antirreumáticos/farmacología , Medio de Cultivo Libre de Suero/toxicidad , Inflamación/prevención & control , Proteína Antagonista del Receptor de Interleucina 1/farmacología , Islotes Pancreáticos/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Humanos , Inflamación/inducido químicamente , Islotes Pancreáticos/patología , Macaca fascicularis , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos
12.
Int J Obes (Lond) ; 41(2): 279-288, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27867203

RESUMEN

BACKGROUND: The exchange protein directly activated by cAMP (Epac), which is primarily involved in cAMP signaling, has been known to be essential for controlling body energy metabolism. Epac has two isoforms: Epac1 and Epac2. The function of Epac1 on obesity was unveiled using Epac1 knockout (KO) mice. However, the role of Epac2 in obesity remains unclear. METHODS: To evaluate the role of Epac2 in obesity, we used Epac2a KO mice, which is dominantly expressed in neurons and endocrine tissues. Physiological factors related to obesity were analyzed: body weight, fat mass, food intake, plasma leptin and adiponectin levels, energy expenditure, glucose tolerance, and insulin and leptin resistance. To determine the mechanism of Epac2a, mice received exogenous leptin and then hypothalamic leptin signaling was analyzed. RESULTS: Epac2a KO mice appeared to have normal glucose tolerance and insulin sensitivity until 12 weeks of age, but an early onset increase of plasma leptin levels and decrease of plasma adiponectin levels compared with wild-type mice. Acute leptin injection revealed impaired hypothalamic leptin signaling in KO mice. Consistently, KO mice fed a high-fat diet (HFD) were significantly obese, presenting greater food intake and lower energy expenditure. HFD-fed KO mice were also characterized by greater impairment of hypothalamic leptin signaling and by weaker leptin-induced decrease in food consumption compared with HFD-fed wild-type mice. In wild-type mice, acute exogenous leptin injection or chronic HFD feeding tended to induce hypothalamic Epac2a expression. CONCLUSIONS: Considering that HFD is an inducer of hypothalamic leptin resistance and that Epac2a functions in pancreatic beta cells during demands of greater work load, hypothalamic Epac2a may have a role in facilitating leptin signaling, at least in response to higher metabolic demands. Thus, our data indicate that Epac2a is critical for preventing obesity and thus Epac2a activators may be used to manage obesity and obesity-mediated metabolic disorders.


Asunto(s)
Metabolismo Energético/fisiología , Factores de Intercambio de Guanina Nucleótido/metabolismo , Hipotálamo/metabolismo , Leptina/farmacología , Obesidad/patología , Receptores de Leptina/metabolismo , Transducción de Señal/fisiología , Animales , AMP Cíclico/fisiología , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Ingestión de Energía , Metabolismo Energético/efectos de los fármacos , Hipotálamo/efectos de los fármacos , Leptina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/efectos de los fármacos
13.
Am J Transplant ; 16(9): 2612-23, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26990829

RESUMEN

Previously, we demonstrated that alemtuzumab induction with rapamycin as sole maintenance therapy is associated with an increased incidence of humoral rejection in human kidney transplant patients. To investigate the role of rapamycin in posttransplant humoral responses after T cell depletion, fully MHC mismatched hearts were transplanted into hCD52Tg mice, followed by alemtuzumab treatment with or without a short course of rapamycin. While untreated hCD52Tg recipients acutely rejected B6 hearts (n = 12), hCD52Tg recipients treated with alemtuzumab alone or in conjunction with rapamycin showed a lack of acute rejection (MST > 100). However, additional rapamycin showed a reduced beating quality over time and increased incidence of vasculopathy. Furthermore, rapamycin supplementation showed an increased serum donor-specific antibodies (DSA) level compared to alemtuzumab alone at postoperation days 50 and 100. Surprisingly, additional rapamycin treatment significantly reduced CD4(+) CD25(+) FoxP3(+) T reg cell numbers during treatment. On the contrary, ICOS(+) PD-1(+) CD4 follicular helper T cells in the lymph nodes were significantly increased. Interestingly, CTLA4-Ig supplementation in conjunction with rapamycin corrected rapamycin-induced accelerated posttransplant humoral response by directly modulating Tfh cells but not Treg cells. This suggests that rapamycin after T cell depletion could affect Treg cells leading to an increase of Tfh cells and DSA production that can be reversed by CTLA4-Ig.


Asunto(s)
Abatacept/farmacología , Formación de Anticuerpos/inmunología , Rechazo de Injerto/inmunología , Trasplante de Corazón , Sirolimus/farmacología , Linfocitos T Reguladores/inmunología , Donantes de Tejidos , Animales , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/metabolismo , Supervivencia de Injerto/inmunología , Inmunosupresores/farmacología , Depleción Linfocítica , Ratones , Ratones Endogámicos C57BL , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/metabolismo
14.
Int J Clin Pract ; 70(4): 302-11, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26997458

RESUMEN

AIM: The aim of this study was to assess the effects of ursodeoxycholic acid composite (URSA-S) on fatigue in patients with elevated liver function tests and/or fatty liver disease. METHODS: In this multi-centre randomised double-blinded placebo-controlled trial, 168 adults who were diagnosed with fatigue based on our criteria and had elevated liver function tests (but not > 5 times the normal level) and/or fatty liver on ultrasonography, were randomised to either the placebo or URSA-S administration group. The rate of improvement of checklist individual strength (CIS) using a cut-off of 76 points at the end of the study (8 weeks), the change in fatigue scale [CIS score and visual analogue scale (VAS)] were evaluated. The adverse effects of URSA-S were also recorded. RESULTS: The rate of CIS improvement at the end-point was 79.76% and 45.68% in the therapy and placebo groups, respectively (p < 0.05). The fatigue recovery rate of the CIS score and VAS were higher in the therapy (-25.44 ± 18.57, -27.84 ± 2.70) than in the placebo group (-16.59 ± 17.29, -19.46 ± 2.81) (p < 0.05). The difference in fatigue recovery rate between the therapy and placebo groups was significant after 8 weeks. When analysed separately in patients with abnormal liver function tests and fatty liver disease, the fatigue recovery rate of the CIS score and VAS at 8 weeks was higher in the therapy than in the placebo group (p < 0.05). The frequency of adverse events in the therapy group was not significantly higher than that in the placebo group. CONCLUSION: URSA-S is effective for alleviating fatigue in patients with liver dysfunction and/or fatty liver. The adverse effects of URSA-S are not significant. This study is registered at https://clinicaltrials.gov/ct2/show/NCT02415777.


Asunto(s)
Fatiga/tratamiento farmacológico , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Ácido Ursodesoxicólico/uso terapéutico , Adulto , Colagogos y Coleréticos/uso terapéutico , Método Doble Ciego , Fatiga/etiología , Fatiga/metabolismo , Femenino , Estudios de Seguimiento , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Estudios Retrospectivos , Resultado del Tratamiento
15.
Am J Transplant ; 15(6): 1543-54, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25865268

RESUMEN

The spheroid culture method is an effective strategy for ex vivo expansion of an autologous therapeutic cell population. We investigated if cotransplantation of bone marrow-derived spheroids (BM-spheroid) formed using 3D culture of BM-derived mononuclear cells (BM-MNCs) could improve the posttransplant outcome of islet grafts using a mouse syngeneic marginal mass renal subcapsular islet transplantation model. Using green fluorescent protein transgenic (GFP-Tg) mice, the role of the BM-spheroids and the contribution of vessels derived from donors and recipients in grafted areas were assessed by immunohistochemistry. Compared to fresh BM-MNCs and nonspheroid remnant cells (BM-nonspheroid), the BM-spheroids, mainly composed of CXCR4(+) CD14(+) myeloid cells, showed higher angiogenic capacity, such as in vitro self-formed vessel structures; increased expression of angiogenic and chemoattractive factors; and incorporation into new vessel formation in basement membrane matrix plugs. BM-spheroid cotransplantation with islets improved the posttransplant outcomes in terms of glucose tolerance, serum insulin level, and diabetes reversal rate when compared with cotransplantation of BM-nonspheroids. Immunohistochemistry revealed that cotransplantation of the BM-spheroids increased vessel density, area of grafted endocrine and non-endocrine tissue, and ß cell proliferation. In conclusion, cotransplantation of islets and BM-spheroids improved islet function through facilitation of revascularization and an increase in cell proliferation and islet cell mass.


Asunto(s)
Células de la Médula Ósea/citología , Células de la Médula Ósea/fisiología , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/irrigación sanguínea , Células Mieloides/citología , Células Mieloides/fisiología , Animales , Glucemia/metabolismo , Comunicación Celular/fisiología , Proliferación Celular/fisiología , Trasplante de Células/métodos , Células Cultivadas , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/cirugía , Modelos Animales de Enfermedad , Supervivencia de Injerto/fisiología , Técnicas In Vitro , Islotes Pancreáticos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neovascularización Fisiológica/fisiología , Estreptozocina/efectos adversos
16.
J Oral Rehabil ; 42(10): 765-73, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26013277

RESUMEN

Effortful swallowing (EFS) is a common compensatory swallowing manoeuver for dysphagia patients. We investigated the influence of EFS on temporal and spatial characteristics of the movements of the hyoid bone, larynx and epiglottis in healthy subjects. A total of 41 volunteers swallowed 10 mL of diluted barium solution using two swallowing strategies: usual and effortful swallowing (USS and EFS). The motions of the hyoid bone, larynx and epiglottis were tracked using frame-by-frame kinematic motion analysis of videofluoroscopic images. Maximal velocities and maximal displacements of hyoid and larynx, the maximal angle of the epiglottic tilt, and the durations of hyoid excursion, laryngeal elevation and epiglottic tilt were measured. Compared to USS, EFS was associated with significantly greater vertical displacement of the hyoid (P < 0.001), vertical and horizontal displacement of the larynx (P = 0.003, P = 0.019), and maximal angle of the epiglottic tilt (P = 0.001). In addition, the durations of the vertical and horizontal excursions of the hyoid, vertical excursion of the larynx and the epiglottic tilt were greater in EFS, compared with USS. Effortful swallowing was also associated with significantly greater maximum velocities of the hyoid and larynx during swallowing. In conclusion, the EFS manoeuver facilitates vertical speed and distance of hyolaryngeal excursion and epiglottic tilt and extends the duration of excursion and the epiglottic tilt, especially after reaching maximal excursion in healthy subjects. These results confirm the temporal and kinematic benefits of airway protection induced by the EFS manoeuver.


Asunto(s)
Deglución/fisiología , Epiglotis/fisiología , Hueso Hioides/fisiología , Laringe/fisiología , Movimiento/fisiología , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Fluoroscopía/métodos , Humanos , Masculino , Persona de Mediana Edad , Grabación en Video , Adulto Joven
17.
N Engl J Med ; 365(1): 32-43, 2011 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-21732835

RESUMEN

BACKGROUND: Nesiritide is approved in the United States for early relief of dyspnea in patients with acute heart failure. Previous meta-analyses have raised questions regarding renal toxicity and the mortality associated with this agent. METHODS: We randomly assigned 7141 patients who were hospitalized with acute heart failure to receive either nesiritide or placebo for 24 to 168 hours in addition to standard care. Coprimary end points were the change in dyspnea at 6 and 24 hours, as measured on a 7-point Likert scale, and the composite end point of rehospitalization for heart failure or death within 30 days. RESULTS: Patients randomly assigned to nesiritide, as compared with those assigned to placebo, more frequently reported markedly or moderately improved dyspnea at 6 hours (44.5% vs. 42.1%, P=0.03) and 24 hours (68.2% vs. 66.1%, P=0.007), but the prespecified level for significance (P≤0.005 for both assessments or P≤0.0025 for either) was not met. The rate of rehospitalization for heart failure or death from any cause within 30 days was 9.4% in the nesiritide group versus 10.1% in the placebo group (absolute difference, -0.7 percentage points; 95% confidence interval [CI], -2.1 to 0.7; P=0.31). There were no significant differences in rates of death from any cause at 30 days (3.6% with nesiritide vs. 4.0% with placebo; absolute difference, -0.4 percentage points; 95% CI, -1.3 to 0.5) or rates of worsening renal function, defined by more than a 25% decrease in the estimated glomerular filtration rate (31.4% vs. 29.5%; odds ratio, 1.09; 95% CI, 0.98 to 1.21; P=0.11). CONCLUSIONS: Nesiritide was not associated with an increase or a decrease in the rate of death and rehospitalization and had a small, nonsignificant effect on dyspnea when used in combination with other therapies. It was not associated with a worsening of renal function, but it was associated with an increase in rates of hypotension. On the basis of these results, nesiritide cannot be recommended for routine use in the broad population of patients with acute heart failure. (Funded by Scios; ClinicalTrials.gov number, NCT00475852.).


Asunto(s)
Disnea/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Natriuréticos/uso terapéutico , Péptido Natriurético Encefálico/uso terapéutico , Readmisión del Paciente/estadística & datos numéricos , Enfermedad Aguda , Anciano , Método Doble Ciego , Disnea/etiología , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/mortalidad , Humanos , Hipotensión/inducido químicamente , Análisis de Intención de Tratar , Enfermedades Renales/etiología , Masculino , Persona de Mediana Edad , Natriuréticos/efectos adversos , Péptido Natriurético Encefálico/efectos adversos , Recurrencia
18.
Angew Chem Int Ed Engl ; 53(40): 10654-7, 2014 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-25130188

RESUMEN

The lithiation/de-lithiation behavior of a ternary oxide (Li2MO3, where M = Mo or Ru) is examined. In the first lithiation, the metal oxide (MO2) component in Li2MO3 is lithiated by a conversion reaction to generate nano-sized metal (M) particles and two equivalents of Li2O. As a result, one idling Li2O equivalent is generated from Li2MO3. In the de-lithiation period, three equivalents of Li2O react with M to generate MO3. The first-cycle Coulombic efficiency is theoretically 150% since the initial Li2MO3 takes four Li(+) ions and four electrons per formula unit, whereas the M component is oxidized to MO3 by releasing six Li(+) ions and six electrons. In practice, the first-cycle Coulombic efficiency is less than 150% owing to an irreversible charge consumption for electrolyte decomposition. The as-generated MO3 is lithiated/de-lithiated from the second cycle with excellent cycle performance and rate capability.

19.
Micromachines (Basel) ; 15(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38675264

RESUMEN

The current commercially used anode material, graphite, has a theoretical capacity of only 372 mAh/g, leading to a relatively low energy density. Lithium (Li) metal is a promising candidate as an anode for enhancing energy density; however, challenges related to safety and performance arise due to Li's dendritic growth, which needs to be addressed. Owing to these critical issues in Li metal batteries, all-solid-state lithium-ion batteries (ASSLIBs) have attracted considerable interest due to their superior energy density and enhanced safety features. Among the key components of ASSLIBs, solid-state electrolytes (SSEs) play a vital role in determining their overall performance. Various types of SSEs, including sulfides, oxides, and polymers, have been extensively investigated for Li metal anodes. Sulfide SSEs have demonstrated high ion conductivity; however, dendrite formation and a limited electrochemical window hinder the commercialization of ASSLIBs due to safety concerns. Conversely, oxide SSEs exhibit a wide electrochemical window, but compatibility issues with Li metal lead to interfacial resistance problems. Polymer SSEs have the advantage of flexibility; however their limited ion conductivity poses challenges for commercialization. This review aims to provide an overview of the distinctive characteristics and inherent challenges associated with each SSE type for Li metal anodes while also proposing potential pathways for future enhancements based on prior research findings.

20.
Am J Transplant ; 13(6): 1429-40, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23601171

RESUMEN

Bone marrow-derived early endothelial progenitor cells (BM-EPCs) are a clinical tool for enhancing revascularization. However, the therapeutic efficacy of co-transplantation of BM-EPC with islets has not been investigated. In this study, marginal mass islets were co-transplanted with or without BM-EPCs under the kidney capsules of syngeneic streptozotocin-induced diabetic mice. Using green fluorescent protein transgenic (GFP-Tg) mice as BM-EPC and islet donors or recipients, the role of EPCs in revascularization was assessed for graft morphology, vascular density and fate of EPCs by immunohistochemistry. Islet-EPC co-transplantation improved the outcome of islet transplantation as measured by glucose tolerance, serum insulin level and diabetes reversal rate, compared with transplantation of islets alone. Between groups, the morphology of islet grafts showed significant differences in size and composition of grafted endocrine tissues. Significantly more vessel density derived from donors and recipients was detected with islet-EPC co-transplantation. Abundant GFP-Tg mice-derived BM-EPCs (GFP-EPCs) were observed in or around islet grafts and incorporated into CD31-positive capillaries. Remaining GFP-EPCs expressed VEGF. In conclusion, co-transplantation of islets with BM-EPCs could improve the outcome of marginal mass islet transplantation by promoting revascularization and preserving islet morphology.


Asunto(s)
Células de la Médula Ósea/citología , Endotelio Vascular/citología , Supervivencia de Injerto/fisiología , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos/irrigación sanguínea , Trasplante de Células Madre/métodos , Células Madre/citología , Animales , Modelos Animales de Enfermedad , Células Endoteliales , Masculino , Ratones , Ratones Endogámicos C57BL
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