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2.
Diagn Interv Imaging ; 99(3): 163-168, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29154015

RESUMEN

OBJECTIVES: The purpose of this study was to compare the albumin-bilirubin (ALBI) grade and model for end-stage liver disease (MELD) scores for predicting survival after transjugular intrahepatic portosystemic shunt (TIPS) creation. MATERIALS AND METHODS: A retrospective study of pre-procedure ALBI and MELD scores was performed in 197 patients who underwent TIPS from 2005 to 2012. There were 140 men and 57 women, with a mean age of 56±11 (SD) (range: 19-90years). The prognostic capability of ALBI and MELD scores were evaluated using competing risks survival analysis. Discriminatory ability was compared between models using the C-index derived from cause specific Cox proportional hazards models. RESULTS: TIPS were created for ascites or hydrothorax (128 patients), variceal hemorrhage (61 patients), or both (8 patients). Prior to TIPS, 5 patients were ALBI grade 1, 76 were grade 2, and 116 were grade 3. The average pre-TIPS MELD score was 14. Pre-TIPS ALBI score, ALBI grade, and MELD were each significant predictors of 30-day mortality from hepatic failure and overall survival (all P<0.05). Based on the C-index, the MELD score was a better predictor of both 30-day and overall survival (C-index=0.74 and 0.63) than either ALBI score (0.70 and 0.59) or ALBI grade (0.64 and 0.56). In multivariate models, after accounting for MELD score ALBI score provided no additional short- or long-term survival information. CONCLUSION: Although ALBI score and grade were statistically significantly associated with risk of death after TIPS, MELD remains the superior predictor.


Asunto(s)
Bilirrubina/sangre , Cirrosis Hepática/mortalidad , Derivación Portosistémica Intrahepática Transyugular , Albúmina Sérica/análisis , Índice de Severidad de la Enfermedad , Adulto , Anciano , Anciano de 80 o más Años , Ascitis/terapia , Femenino , Hemorragia/terapia , Humanos , Hidrotórax/terapia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
3.
Aliment Pharmacol Ther ; 47(2): 268-278, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29115682

RESUMEN

BACKGROUND: With its increasing incidence, nonalcoholic fatty liver disease (NAFLD) is of particular concern in the Veterans Health Administration (VHA). AIMS: To evaluate risk factors for advanced fibrosis in biopsy-proven NAFLD in the VHA, to identify patients at risk for adverse outcomes. METHODS: In randomly selected cases from VHA databases (2005-2015), we performed a retrospective case-control study in adults with biopsy-defined NAFLD or normal liver. RESULTS: Of 2091 patients reviewed, 399 met inclusion criteria. Normal controls (n = 65) had normal liver function. The four NAFLD cohorts included: NAFL steatosis (n = 76), nonalcoholic steatohepatitis (NASH) without fibrosis (n = 68), NAFLD/NASH stage 1-3 fibrosis (n = 82), and NAFLD/NASH cirrhosis (n = 70). NAFLD with hepatocellular carcinoma (HCC) was separately identified (n = 38). Most patients were older White men. NAFLD patients with any fibrosis were on average severely obese (BMI>35 kg/m2 ). Diabetes (54.4%-79.6%) and hypertension (85.8%-100%) were more common in NAFLD with fibrosis or HCC. Across NAFLD, 12.3%-19.5% were enrolled in diet/exercise programs and 0%-2.6% had bariatric surgery. Hispanics exhibited higher rates of NASH (20.6%), while Blacks had low NAFLD rates (1.4%-11.8%), particularly NAFLD cirrhosis and HCC (1.4%-2.6%). Diabetes (OR 11.8, P < .001) and BMI (OR 1.4, P < .001) were the most significant predictors of advanced fibrosis. CONCLUSIONS: In the VHA, diabetes and severe obesity increased risk for advanced fibrosis in NAFLD. Of these patients, only a small proportion (~20%) had enrolled in diet/exercise programs or had bariatric surgery (~2%). These results suggest that providers should focus/tailor interventions to improve outcomes, particularly in those with diabetes and severe obesity.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/patología , Veteranos/estadística & datos numéricos , Adulto , Anciano , Biopsia/métodos , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/epidemiología , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Cirrosis Hepática/epidemiología , Cirrosis Hepática/etiología , Cirrosis Hepática/patología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/epidemiología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Estados Unidos/epidemiología , United States Department of Veterans Affairs , Salud de los Veteranos
4.
Acta Anaesthesiol Scand ; 61(6): 668-675, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28573655

RESUMEN

BACKGROUND: This study investigated whether pain and pain-related unpleasantness ratings were altered by blood testosterone levels. We also investigated whether activation of brain regions that represent pain intensity [primary somatosensory cortex (S1)] and pain-related unpleasantness [perigenual ACC (pACC) and orbitofrontal cortex (OFC)] were affected by blood testosterone levels. METHODS: Twenty-six healthy men were recruited. Blood testosterone levels were measured before fMRI scanning. The participants were classified into two groups (high vs. low testosterone) according to their blood testosterone level (each group n = 13). The middle finger was immersed in a 50°C water bath (50°C, 30 s, five times) to induce identical noxious stimulation in all participants. RESULTS: The low testosterone group showed statistically significantly higher pain (P = 0.047), unpleasantness (P = 0.047), anxiety (P = 0.015), and fear ratings (P = 0.01) than the high testosterone group. Fear rating increased as pain rating rose and as testosterone level decreased (P < 0.001). When participants received noxious stimulation, the pACC and OFC were more highly activated in the low testosterone group compared to the high testosterone group. Activation of S1, a region related to pain intensity, did not differ between both groups. CONCLUSION: Compared to the high testosterone group, the low testosterone group had significant activation in the pACC and OFC, regions that represent pain-related unpleasantness, but not in S1 that represents pain intensity, leading to higher pain ratings. These findings emphasize the importance of considering the effects of testosterone levels when treating patients.


Asunto(s)
Encéfalo/fisiopatología , Dolor/psicología , Testosterona/sangre , Adulto , Corteza Cerebral/fisiopatología , Miedo/psicología , Voluntarios Sanos , Calor , Humanos , Imagen por Resonancia Magnética , Masculino , Dolor/fisiopatología , Dimensión del Dolor , Corteza Prefrontal/fisiopatología , Corteza Somatosensorial/fisiopatología , Adulto Joven
5.
Eye (Lond) ; 30(8): 1135-43, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27229708

RESUMEN

PurposeTo characterize the rod and cone photoreceptor mosaic at retinal locations spanning the central 60° in vivo using adaptive optics scanning laser ophthalmoscopy (AO-SLO) in healthy human eyes.MethodsAO-SLO images (0.7 × 0.9°) were acquired at 680 nm from 14 locations from 30° nasal retina (NR) to 30° temporal retina (TR) in 5 subjects. Registered averaged images were used to measure rod and cone density and spacing within 60 × 60 µm regions of interest. Voronoi analysis was performed to examine packing geometry at all locations.ResultsAverage peak cone density near the fovea was 164 000±24 000 cones/mm(2) and decreased to 6700±1500 and 5400±700 cones/mm(2) at 30° NR and 30° TR, respectively. Cone-to-cone spacing increased from 2.7±0.2 µm at the fovea to 14.6±1.4 µm at 30° NR and 16.3±0.7 µm at 30° TR. Rod density peaked at 25° NR (124 000±20 000 rods/mm(2)) and 20° TR (120 000±12 000 rods/mm(2)) and decreased at higher eccentricities. Center-to-center rod spacing was lowest nasally at 25° (2.1±0.1 µm). Temporally, rod spacing was lowest at 20° (2.2±0.1 µm) before increasing to 2.3±0.1 µm at 30° TR.ConclusionsBoth rod and cone densities showed good agreement with histology and prior AO-SLO studies. The results demonstrate the ability to image at higher retinal eccentricities than reported previously. This has clinical importance in diseases that initially affect the peripheral retina such as retinitis pigmentosa.


Asunto(s)
Células Fotorreceptoras Retinianas Conos/citología , Células Fotorreceptoras Retinianas Bastones/citología , Adulto , Longitud Axial del Ojo/anatomía & histología , Recuento de Células , Fóvea Central/anatomía & histología , Voluntarios Sanos , Humanos , Oftalmoscopía/métodos , Adulto Joven
6.
Transplant Proc ; 48(1): 102-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26915851

RESUMEN

BACKGROUND: Concerns about the adverse effects of hydroxyethyl starch (HES) on renal function have been raised in recent studies involving critically ill patients. We aimed to evaluate the effect of HES on acute kidney injury (AKI) after living donor right hepatectomy. METHODS: We performed a 1:3 propensity score matching analysis of the medical records of 1641 living donors who underwent a donor right hepatectomy. They were divided into the control group (n = 60), who received only crystalloids, and the colloid group (n = 1,581), who received HES 130/0.4 and crystalloids. Postoperative AKI was determined by AKI Network (AKIN) and Risk, Injury, Failure, Loss, End-stage (RIFLE) criteria. RESULTS: A 1:3 propensity score matching was performed in 206 donors, 54 donors in the control group and 152 donors in the colloid group. For the matched colloid group, the median amount of 7.65 mL/kg (interquartile range, 6.64-9.20) of colloid and 58.19 mL/kg (interquartile range, 45.63-71.51) of crystalloid were given. The median amount of administered crystalloid in the control group was 56.48 mL/kg (interquartile range, 47.94-76.12) after propensity score matching. The incidences of AKI were not different between the control and colloid groups (P = .460 by AKIN criteria; P = .999 by RIFLE criteria). CONCLUSION: Intraoperative administration of HES may not be associated with AKI after living donor hepatectomy. This result can provide useful information on perioperative fluid management in living liver donors.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Hepatectomía/métodos , Derivados de Hidroxietil Almidón/efectos adversos , Donadores Vivos , Sustitutos del Plasma/efectos adversos , Recolección de Tejidos y Órganos/métodos , Lesión Renal Aguda/epidemiología , Adulto , Anciano , Estudios de Casos y Controles , Soluciones Cristaloides , Femenino , Fluidoterapia/efectos adversos , Humanos , Incidencia , Soluciones Isotónicas/efectos adversos , Trasplante de Hígado/métodos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Puntaje de Propensión
7.
Acta Anaesthesiol Scand ; 60(2): 193-202, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26830214

RESUMEN

BACKGROUND: The safety of healthy living donors who are undergoing hepatic resection is a primary concern. We aimed to identify intraoperative anaesthetic and surgical factors associated with delayed recovery of liver function after hepatectomy in living donors. METHODS: We retrospectively analysed 1969 living donors who underwent hepatectomy for living donor liver transplantation. Delayed recovery of hepatic function was defined by increases in international normalised ratio of prothrombin time and concomitant hyperbilirubinaemia on or after post-operative day 5. Univariate and multivariate logistic regression analyses were performed to determine the factors associated with delayed recovery of hepatic function after living donor hepatectomy. RESULTS: Delayed recovery of liver function after donor hepatectomy was observed in 213 (10.8%) donors. Univariate logistic regression analysis showed that sevoflurane anaesthesia, synthetic colloid, donor age, body mass index, fatty change and remnant liver volume were significant factors for prediction of delayed recovery of hepatic function. Multivariate logistic regression analysis showed that independent factors significantly associated with delayed recovery of liver function after donor hepatectomy were sevoflurane anaesthesia (odds ratio = 3.514, P < 0.001), synthetic colloid (odds ratio = 1.045, P = 0.033), donor age (odds ratio = 0.970, P = 0.003), female gender (odds ratio = 1.512, P = 0.014) and remnant liver volume (odds ratio = 0.963, P < 0.001). CONCLUSIONS: Anaesthesia with sevoflurane was an independent factor in predicting delayed recovery of hepatic function after donor hepatectomy. Although synthetic colloid may be associated with delayed recovery of hepatic function after donor hepatectomy, further study is required. These results can provide useful information on perioperative management of living liver donors.


Asunto(s)
Hepatectomía , Trasplante de Hígado , Hígado/fisiopatología , Donadores Vivos , Recuperación de la Función , Adulto , Coloides/administración & dosificación , Femenino , Humanos , Modelos Logísticos , Masculino , Éteres Metílicos/farmacología , Monitoreo Intraoperatorio , Estudios Retrospectivos , Sevoflurano
8.
Acta Anaesthesiol Scand ; 60(6): 747-55, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26846426

RESUMEN

BACKGROUND: Current methods for verification of endotracheal intubation can fail, particularly in emergency settings. We investigated whether a verification method using electrical stimulation through electrodes placed on the endotracheal tube cuff could distinguish endotracheal and esophageal intubations in an experimental setting. METHODS: During three sequential sessions simulating emergency intubation without paralysis, rapid sequence intubation (RSI) with neuromuscular blockade, and intubation during cardiopulmonary resuscitation, eight pigs were intubated with an endotracheal tube fitted with two electrodes exposed on the cuff of the tube, first in the esophagus and next in the trachea or in reverse sequence. Cuff pressure was monitored during a 5-s electrical stimulation (20 mA, 80 Hz, 500 µs), and delta pressure was calculated as the difference between baseline cuff pressure and maximum cuff pressure during the electrical stimulation. RESULTS: Delta pressure was significantly higher in esophageal than in tracheal placements in all three sequential sessions (86.0 [78.3-89.7] vs. 6.5 [2.0-7.9] mmHg, P = 0.001; 16.6 [13.2-22.8] vs. 0.8 [0.3-2.6] mmHg, P = 0.004; 66.1 [60.0-84.7] vs. 2.7 [0.7-9.7] mmHg, P = 0.001). The delta pressure did not overlap between tracheal and esophageal intubations except for the session simulating RSI with neuromuscular blockade, in which one of eight esophageal placements showed a delta pressure within the delta pressure range of tracheal placements. CONCLUSION: Electrical stimulation through electrodes placed on the endotracheal tube cuff produced remarkably greater increases in cuff pressure in esophageal intubations than in tracheal intubations in an experimental setting.


Asunto(s)
Estimulación Eléctrica , Esófago , Intubación Intratraqueal/instrumentación , Intubación Intratraqueal/métodos , Tráquea , Animales , Electrodos , Porcinos
9.
Anaesthesia ; 70(11): 1250-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26215206

RESUMEN

Reducing blood loss is beneficial in living liver donor hepatectomy. Although it has been suggested that maintaining a low central venous pressure is important, it is known that low stroke volume variation may be associated with increased blood loss. Therefore, we compared the effect on blood loss of 40 patients randomly assigned to a high stroke volume variation group (maintaining 10-20% of stroke volume variation) vs 38 patients in a control group (maintaining < 10% stroke volume variation) during living-donor right hepatectomy. Mean (SD) blood loss during donor hepatectomy was significantly lower in the high stroke volume variation group than in the control group: 476 (131) ml vs 836 (341) ml, respectively (p < 0.001). Blood pressure and peri-operative laboratory values did not differ between the two groups. However, in the high stroke volume variation group, central venous pressure values were also significantly lower. We were unable to disentangle the effects of stroke volume variation and central venous pressure, but our results confirm that the two together appear beneficial.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Fluidoterapia/métodos , Hepatectomía , Trasplante de Hígado , Donadores Vivos , Volumen Sistólico/fisiología , Adulto , Femenino , Humanos , Masculino , Adulto Joven
10.
Gut ; 64(7): 1120-31, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24902765

RESUMEN

BACKGROUND: Chronic liver injury triggers a progenitor cell repair response, and liver fibrosis occurs when repair becomes deregulated. Previously, we reported that reactivation of the hedgehog pathway promotes fibrogenic liver repair. Osteopontin (OPN) is a hedgehog-target, and a cytokine that is highly upregulated in fibrotic tissues, and regulates stem-cell fate. Thus, we hypothesised that OPN may modulate liver progenitor cell response, and thereby, modulate fibrotic outcomes. We further evaluated the impact of OPN-neutralisation on murine liver fibrosis. METHODS: Liver progenitors (603B and bipotential mouse oval liver) were treated with OPN-neutralising aptamers in the presence or absence of transforming growth factor (TGF)-ß, to determine if (and how) OPN modulates liver progenitor function. Effects of OPN-neutralisation (using OPN-aptamers or OPN-neutralising antibodies) on liver progenitor cell response and fibrogenesis were assessed in three models of liver fibrosis (carbon tetrachloride, methionine-choline deficient diet, 3,5,-diethoxycarbonyl-1,4-dihydrocollidine diet) by quantitative real time (qRT) PCR, Sirius-Red staining, hydroxyproline assay, and semiquantitative double-immunohistochemistry. Finally, OPN expression and liver progenitor response were corroborated in liver tissues obtained from patients with chronic liver disease. RESULTS: OPN is overexpressed by liver progenitors in humans and mice. In cultured progenitors, OPN enhances viability and wound healing by modulating TGF-ß signalling. In vivo, OPN-neutralisation attenuates the liver progenitor cell response, reverses epithelial-mesenchymal-transition in Sox9+ cells, and abrogates liver fibrogenesis. CONCLUSIONS: OPN upregulation during liver injury is a conserved repair response, and influences liver progenitor cell function. OPN-neutralisation abrogates the liver progenitor cell response and fibrogenesis in mouse models of liver fibrosis.


Asunto(s)
Cirrosis Hepática/metabolismo , Osteopontina/metabolismo , Células Madre/metabolismo , Animales , Progresión de la Enfermedad , Regulación hacia Abajo/fisiología , Inmunohistoquímica , Hígado/patología , Cirrosis Hepática/patología , Ratones Endogámicos C57BL , Factor de Transcripción SOX9/metabolismo , Factor de Crecimiento Transformador beta/fisiología , Regulación hacia Arriba/fisiología , Cicatrización de Heridas/fisiología
11.
Nat Mater ; 13(8): 817-21, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24880732

RESUMEN

Liquid-crystalline polymers are materials of considerable scientific interest and technological value. An important subset of these materials exhibit rubber-like elasticity, combining the optical properties of liquid crystals with the mechanical properties of rubber. Moreover, they exhibit behaviour not seen in either type of material independently, and many of their properties depend crucially on the particular mesophase employed. Such stretchable liquid-crystalline polymers have previously been demonstrated in the nematic, chiral-nematic, and smectic mesophases. Here, we report the fabrication of a stretchable gel of blue phase I, which forms a self-assembled, three-dimensional photonic crystal that remains electro-optically switchable under a moderate applied voltage, and whose optical properties can be manipulated by an applied strain. We also find that, unlike its undistorted counterpart, a mechanically deformed blue phase exhibits a Pockels electro-optic effect, which sets out new theoretical challenges and possibilities for low-voltage electro-optic devices.


Asunto(s)
Geles/química , Cristales Líquidos/química , Elasticidad , Electroquímica/métodos , Óptica y Fotónica , Fotones , Física/métodos , Polímeros/química , Temperatura
12.
Folia Morphol (Warsz) ; 73(2): 153-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24902093

RESUMEN

The vascular content of retrodiscal tissue in the temporomandibular joint (TMJ) plays a critical role in joint function, and its morphology is therefore likely relatedto TMJ pain. Using histological sections of human foetuses as well as T2-weighted magnetic resonance images (MRI), we measured the vascular content of retrodiscal tissue. MRI showing no pathology in and around the TMJ were obtained from18 young patients who had been suffering from headache. In 10 small foetuses (12-14 weeks of gestation) as well as 10 larger foetuses (30-37 weeks), the vascular content showed individual variations exceeding 5 times the minimum value (0.24 vs. 0.04 mm2 per 1 mm²), but no difference between foetal stages was evident. In the MRI from young adults, the variation was less than twice the minimum value (13.6 vs. 8.7 mm² per 100 mm²). The vascular density appeared to be lower in adults than in foetuses. In both foetuses and adults, the thickness (anteroposterior length) of the tissue did not correlate with the vascular sectional area. These findings suggest that the considerable inter-individual differences evident in the vascular content of foetal retrodiscal tissue may be reduced during further development.

13.
Gut ; 63(8): 1333-44, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24173292

RESUMEN

OBJECTIVE: Smoothened (SMO), a coreceptor of the Hedgehog (Hh) pathway, promotes fibrogenic repair of chronic liver injury. We investigated the roles of SMO+ myofibroblast (MF) in liver regeneration by conditional deletion of SMO in α smooth muscle actin (αSMA)+ cells after partial hepatectomy (PH). DESIGN: αSMA-Cre-ER(T2)×SMO/flox mice were treated with vehicle (VEH) or tamoxifen (TMX), and sacrificed 24-96 h post-PH. Regenerating livers were analysed for proliferation, progenitors and fibrosis by qRT-PCR and quantitative immunohistochemistry (IHC). Results were normalised to liver segments resected at PH. For lineage-tracing studies, αSMA-Cre-ER(T2)×ROSA-Stop-flox-yellow fluorescent protein (YFP) mice were treated with VEH or TMX; livers were stained for YFP, and hepatocytes isolated 48 and 72 h post-PH were analysed for YFP by flow cytometric analysis (FACS). RESULTS: Post-PH, VEH-αSMA-SMO mice increased expression of Hh-genes, transiently accumulated MF, fibrosis and liver progenitors, and ultimately exhibited proliferation of hepatocytes and cholangiocytes. In contrast, TMX-αSMA-SMO mice showed loss of whole liver SMO expression, repression of Hh-genes, enhanced accumulation of quiescent HSC but reduced accumulation of MF, fibrosis and progenitors, as well as inhibition of hepatocyte and cholangiocyte proliferation, and reduced recovery of liver weight. In TMX-αSMA-YFP mice, many progenitors, cholangiocytes and up to 25% of hepatocytes were YFP+ by 48-72 h after PH, indicating that liver epithelial cells were derived from αSMA-YFP+ cells. CONCLUSIONS: Hh signalling promotes transition of quiescent hepatic stellate cells to fibrogenic MF, some of which become progenitors that regenerate the liver epithelial compartment after PH. Hence, scarring is a component of successful liver regeneration.


Asunto(s)
Hepatectomía , Células Estrelladas Hepáticas/metabolismo , Hepatocitos/metabolismo , Regeneración Hepática/fisiología , Miofibroblastos/metabolismo , Receptores Acoplados a Proteínas G/análisis , Transducción de Señal , Células Madre/metabolismo , Actinas/metabolismo , Animales , Antineoplásicos Hormonales/farmacología , Fibrosis/metabolismo , Expresión Génica/efectos de los fármacos , Proteínas Hedgehog/genética , Inmunohistoquímica , Regeneración Hepática/efectos de los fármacos , Proteínas Luminiscentes , Ratones , Receptores Acoplados a Proteínas G/genética , Transducción de Señal/efectos de los fármacos , Receptor Smoothened , Tamoxifeno/farmacología
14.
Nat Mater ; 11(7): 599-603, 2012 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-22581313

RESUMEN

A promising approach to the fabrication of materials with nanoscale features is the transfer of liquid-crystalline structure to polymers. However, this has not been achieved in systems with full three-dimensional periodicity. Here we demonstrate the fabrication of self-assembled three-dimensional nanostructures by polymer templating blue phase I, a chiral liquid crystal with cubic symmetry. Blue phase I was photopolymerized and the remaining liquid crystal removed to create a porous free-standing cast, which retains the chiral three-dimensional structure of the blue phase, yet contains no chiral additive molecules. The cast may in turn be used as a hard template for the fabrication of new materials. By refilling the cast with an achiral nematic liquid crystal, we created templated blue phases that have unprecedented thermal stability in the range -125 to 125 °C, and that act as both mirrorless lasers and switchable electro-optic devices. Blue-phase templated materials will facilitate advances in device architectures for photonics applications in particular.

15.
Br J Radiol ; 84(1007): e213-6, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22011825

RESUMEN

Synovial chondromatosis of the temporomandibular joint is a rare benign joint disorder that has been reported in only a few studies. However, we recently encountered a pathologically proven case of this disorder. This case also showed the typical imaging findings on panoramic radiographs and on CT and MR images. Therefore, we report this case and the imaging and pathological findings.


Asunto(s)
Calcinosis/diagnóstico , Condromatosis Sinovial/diagnóstico , Imagen por Resonancia Magnética , Trastornos de la Articulación Temporomandibular/diagnóstico , Tomografía Computarizada por Rayos X , Calcinosis/complicaciones , Condromatosis Sinovial/complicaciones , Condromatosis Sinovial/patología , Condromatosis Sinovial/cirugía , Dolor Facial/etiología , Dolor Facial/cirugía , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Articulación Temporomandibular/patología , Trastornos de la Articulación Temporomandibular/cirugía , Resultado del Tratamiento
16.
Clin Lab ; 57(1-2): 59-65, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21391466

RESUMEN

BACKGROUND: The present study was carried out to describe the epidemiologic characteristics of viral gastroenteritis and determine the phylogenetic composition of norovirus strains detected in hospitalized children with acute gastroenteritis in Seoul, Korea. METHODS AND RESULTS: In total, 10,603 stool samples were collected from 2004 to 2008 and tested by RT-PCR or ELISA. In 4,170 (39.3%) samples at least one viral pathogen was present. Rotavirus (RoV) (1,864, 17.5%) was found to be the causative agent followed by norovirus (NoV) (1,845, 17.4%), human adenovirus (HAdV) (266, 2.5%), human astrovirus (HAstV) (194, 1.8%), and sapovirus (SV) (1, 0.009%). Five GI genotypes (GI-1, GI-3, GI-4, GI-8, and GI-9) and eight GII genotypes (GII-2, GII-3, GII-4, GII-6, GII-7, GII-12, GII-16, and GII-17) of NoV were identified in acute gastroenteritis patients in 2008. CONCLUSIONS: The genetic characteristics of norovirus and the epidemiologic patterns of a viral pathogen from acute gastroenteritis patients may give potentially effective data for epidemiological studies in Seoul, Korea.


Asunto(s)
Gastroenteritis/virología , Virosis/virología , Preescolar , Ensayo de Inmunoadsorción Enzimática , Heces/virología , Femenino , Gastroenteritis/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Norovirus/genética , Norovirus/aislamiento & purificación , Filogenia , República de Corea , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Eye (Lond) ; 25(6): 775-83, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21436847

RESUMEN

PURPOSE: The purpose of this study is to evaluate the macular morphological changes associated with idiopathic epiretinal membrane (iERM) using high-resolution Fourier-domain optical coherence tomography (FD-OCT), as they correlate with visual acuity and microperimetry (MP-1). METHODS: In all, 24 eyes (19 subjects) with iERM were imaged prospectively using FD-OCT with axial resolution of 4.5 µm and transverse resolution of 10 to 15 µm. MP-1 and Stratus OCT were carried out in a subset of eyes. RESULTS: The mean log of the minimum angle of resolution best-corrected visual acuity (BCVA) was 0.18±0.16 (range: -0.08 to 0.48, Snellen equivalent 20/15(-1) to 20/60). ERM was visualized in all 24 eyes with FD-OCT and in 17 eyes (85%) of 20 eyes imaged with Stratus OCT. Although BCVA correlated with macular thickening in the central 1 mm sub-field of the Stratus ETDRS (P=0.0005) and macular volume (central 3 mm area) on FD-OCT (P<0.0001), macular thickening on thickness map and volume correlated poorly with decrease in macular sensitivity on MP-1 (P=0.16). On FD-OCT, foveal morphological changes correlated best with decrease in BCVA, the strongest being central foveal thickness (P<0.0001). Other significant changes included blurring of the foveal inner segment-outer segment (IS-OS) junction and/or Verhoeff's membrane, vitreal displacement of foveal outer nuclear layer and foveal detachment (P<0.05). Foveal IS-OS junction disruption was seen in 25% of eyes on Stratus OCT but in none of the eyes on FD-OCT. CONCLUSION: FD-OCT allowed improved visualization of ERM and associated foveal morphological changes that correlated best with BCVA. Macular thickening correlated weakly with decreased macular function as assessed by MP-1.


Asunto(s)
Membrana Epirretinal/fisiopatología , Mácula Lútea/patología , Agudeza Visual/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Análisis de Fourier , Humanos , Mácula Lútea/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tomografía de Coherencia Óptica/métodos , Campos Visuales/fisiología
18.
Transplant Proc ; 43(1): 170-3, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21335179

RESUMEN

BACKGROUND: QT interval prolongation, predisposing to ventricular tachyarrhythmia, has frequently been observed in patients with liver cirrhosis. During liver transplantation (LT) surgery, electrolyte imbalance and hemodynamic instability may affect QT interval changes. We evaluated the alterations in QT parameters at each stage of LT surgery. METHODS: We assessed 50 living donor LT recipients without overt heart disease for the corrected QT (QTc) and the interval from peak to the end of the T wave (T(p-e)) automatically using Bazett's formula with LabChart software. QT parameters, laboratory and hemodynamic data were simultaneously collected in the following stages of LT: before anesthetic induction (baseline), pre-anhepatic, anhepatic, 1 hour postreperfusion, and after hepatic artery anastomosis. Recipients were allocated into 2 groups according to their baseline QTc: ≥440 versus <440 msec. RESULTS: QTc progressively rose from the pre-anhepatic stage remaining prolonged in each stage of LT surgery compared with the baseline. In the anhepatic stage, 54% of recipients showed marked prolongation of QTc ≥500 msec (522 ± 14), which indicated the potential for a fatal ventricular dysrhythmia: 77% and 36% in groups with QTc ≥440 and <440 msec, respectively. As opposed to changes in QTc, T(p-e) in the anhepatic stage decreased significantly; however, it returned to the baseline level in the neohepatic stage. CONCLUSION: A prolonged QTc interval (≥500 msec) was frequently observed throughout the procedure of LT, even among patients with baseline QTc <440 msec, emphasizing the importance of optimizing electrolyte balance and hemodynamic status to reduce greater risk of perioperative arrhythmias.


Asunto(s)
Electrocardiografía , Trasplante de Hígado , Donadores Vivos , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Eye (Lond) ; 25(3): 279-89, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21293495

RESUMEN

Inner and outer retinal morphology were quantified in vivo for 6 nonglaucomatous and 10 glaucomatous optic neuropathy patients. Custom, ultrahigh-resolution imaging modalities were used to evaluate segmented retinal layer thickness in 3D volumes (Fourier-domain optical coherence tomography), cone photoreceptor density (adaptive optics fundus camera), and the length of inner and outer segments of cone photoreceptors (adaptive optics-optical coherence tomography). Quantitative comparisons were made with age-matched controls, or by comparing affected and nonaffected retinal areas defined by changes in visual fields. The integrity of outer retinal layers on optical coherence tomography B-scans and density of cone photoreceptors were correlated with visual field sensitivity at corresponding retinal locations following reductions in inner retinal thickness. The photoreceptor outer segments were shorter and exhibited greater variability in retinal areas associated with visual field losses compared with normal or less affected areas of the same patient's visual field. These results demonstrate that nonglaucomatous and glaucomatous optic neuropathies are associated with outer retinal changes following long-term inner retinal pathology.


Asunto(s)
Glaucoma/patología , Enfermedades del Nervio Óptico/patología , Retina/anomalías , Retina/patología , Adulto , Anciano , Femenino , Glaucoma/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Nervio Óptico/fisiopatología , Tomografía de Coherencia Óptica/métodos , Campos Visuales/fisiología , Adulto Joven
20.
Clin Lab ; 57(11-12): 959-67, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22239028

RESUMEN

BACKGROUND: Human enteroviruses (HEVs) are a major cause of herpangina, HFMD (hand, foot, and mouth disease), and other neurological diseases in Seoul, Korea. METHODS: A total of 56 specimens from hospitalized patients collected from February to December 2009 (37 females and 19 males) in Seoul were tested for HEV from stool, throat swab, and vesicle swab samples taken from patients with herpangina or HFMD using cell culture and RT-PCR in 2009. By the 1D gene, encoding the VP1 capsid protein, seven different HEV genotypes were detected with Coxsackievirus A2, A4, A5, A9, A16 (CA), Coxsackievirus B1 (CB), and Enterovirus 71 (EV71). The most prevalent genotype was CA16 (6, 10.7%), followed by CA2 (4, 7.1%), CA5 (4, 7.1%), EV71 (2, 3.6%), CA4 (1, 1.8%), CA9 (1, 1.8%), and CB1 (1, 1.8%). The 1D gene sequences of two EV71 strains were closely related with one another (98.5% nucleotide similarity) and belonged to the C4 genotype. CONCLUSIONS: It is important to continuously survey the genetic characteristics of EV71 and CA16 from patients, which will provide useful data that aids in our understanding of HFMD infections in Seoul, Korea and may contribute to future control.


Asunto(s)
Infecciones por Coxsackievirus/virología , Brotes de Enfermedades , Infecciones por Enterovirus/virología , Enterovirus/aislamiento & purificación , Enfermedad de Boca, Mano y Pie/virología , Herpangina/virología , Proteínas de la Cápside/genética , Preescolar , Infecciones por Coxsackievirus/epidemiología , Enterovirus/genética , Enterovirus Humano A/genética , Enterovirus Humano A/aislamiento & purificación , Enterovirus Humano B/genética , Enterovirus Humano B/aislamiento & purificación , Infecciones por Enterovirus/epidemiología , Heces/virología , Femenino , Enfermedad de Boca, Mano y Pie/epidemiología , Herpangina/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Faringe/virología , Filogenia , ARN Viral/genética , ARN Viral/aislamiento & purificación , República de Corea/epidemiología , Análisis de Secuencia de ARN
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