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2.
J Med Internet Res ; 24(12): e40370, 2022 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-36382349

RESUMEN

BACKGROUND: In the second stage of the Electronic Health Record Sharing System (eHRSS) development, a mobile app (eHealth app) was launched to further enhance collaborative care among the public sector, the private sector, the community, and the caregivers. OBJECTIVE: This study aims to investigate the factors associated with the downloading and utilization of the app, as well as the awareness, perception, and future improvement of the app. METHODS: We collected 2110 surveys; respondents were stratified into 3 groups according to their status of enrollment in the eHRSS. The primary outcome measure was the downloading and acceptance of the eHealth app. We collected the data on social economics factors, variables of the Technology Acceptance Model and Theory of Planned Behavior. Any factors identified as significant in the univariate analysis (P<.20) will be included in a subsequent multivariable regression analysis model. All P values ≤.05 will be considered statistically significant in multiple logistic regression analysis. The structural equation modeling was performed to identify interactions among the variables. RESULTS: The respondents had an overall high satisfaction rate and a positive attitude toward continuing to adopt and recommend the app. However, the satisfaction rate among respondents who have downloaded but not adopted the app was relatively lower, and few of them perceived that the downloading and acceptance processes are difficult. A high proportion of current users expressed a positive attitude about continuing to adopt and recommend the app to friends, colleagues, and family members. The behavioral intention strongly predicted the acceptance of the eHealth app (ß=.89; P<.001). Attitude (ß=.30; P<.001) and perceived norm; ß=.37; P<.001) played important roles in determining behavioral intention, which could predict the downloading and acceptance of the eHealth app (ß=.14; P<.001). CONCLUSIONS: Despite the high satisfaction rate among the respondents, privacy concerns and perceived difficulties in adopting the app were the major challenges of promoting eHealth. Further promotion could be made through doctors and publicity. For future improvement, comprehensive health records and tailored health information should be included.


Asunto(s)
Aplicaciones Móviles , Telemedicina , Humanos , Registros Electrónicos de Salud , Intención , Encuestas y Cuestionarios
3.
Ann Hematol ; 101(6): 1163-1172, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35412083

RESUMEN

The thrombopoietin mimetic eltrombopag (EPAG) is efficacious in clinical trials of newly diagnosed moderate (M), severe (S) and very severe (vS) aplastic anaemia (AA). Its use in routine practice and resource-constrained settings is not well described. Twenty-five men and 38 women at a median age of 54 (18-86) years with newly diagnosed AA treated consecutively in a 7-year period with EPAG (N = 6), EPAG/cyclosporine (CsA) (N = 33) and EPAG/CsA/anti-thymocyte globulin (ATG) (N = 24) were analyzed. Because EPAG was not reimbursed, peak doses ranged from 25 to 200 mg/day depending on affordability. EPAG/CsA-treated patients were older (median age: 61 years) with less severe AA (MAA, N = 15; SAA, N = 14; vSAA, N = 4), whereas EPAG/CsA/ATG-treated patients were younger (median age: 44 years) with more severe AA (MAA, N = 2; SAA, N = 12, vSAA, N = 10). The overall/trilineage response rates were 83%/50% for EPAG-treated patients; 79%/42% for EPAG/CsA-treated patients and 75%/63% for EPAG/CsA/ATG-treated patients. Adverse events included grade 1 liver derangement (N = 7) and grade 1 dyspepsia (N = 3). The 5-year overall survivals/failure-free survivals were 62%/80% for the entire cohort; 55%/75% for EPAG/CsA-treated patients and 82%/78% for EPAG/CsA/ATG-treated patients. EPAG showed robust efficacy in AA in routine practice. However, EPAG dosage and combinations remain to be optimized for AA of different severities.


Asunto(s)
Anemia Aplásica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anemia Aplásica/inducido químicamente , Anemia Aplásica/tratamiento farmacológico , Suero Antilinfocítico/uso terapéutico , Benzoatos/efectos adversos , Ciclosporina/uso terapéutico , Femenino , Humanos , Hidrazinas/efectos adversos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Pirazoles , Resultado del Tratamiento , Adulto Joven
5.
Adv Sci (Weinh) ; 6(24): 1901822, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31871862

RESUMEN

Substantia nigra (SN) is a complex and critical region of the brain wherein Parkinson's disease (PD) arises from the degeneration of dopaminergic neurons. Miniature SN-like structures (mini-SNLSs) constructed from novel combination of nanomaterials and cell technologies exhibit promise as potentially curative cell therapies for PD. In this work, a rapid self-organization of mini-SNLS, with an organizational structure and neuronal identities similar to those of the SN in vivo, is achieved by differentiating neural stem cells in vitro on biocompatible silica nanozigzags (NZs) sculptured by glancing angle deposition, without traditional chemical growth factors. The differentiated neurons exhibit electrophysiological activity in vitro. Diverse physical cues and signaling pathways that are determined by the nanomatrices and lead to the self-organization of the mini-SNLSs are clarified and elucidated. In vivo, transplantation of the neurons from a mini-SNLS results in an early and progressive amelioration of PD in rats. The sculptured medical device reported here enables the rapid and specific self-organization of region-specific and functional brain-like structures without an undesirable prognosis. This development provides promising and significant insights into the screening of potentially curative drugs and cell therapies for PD.

6.
Ann Emerg Med ; 72(5): 534-543, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30037583

RESUMEN

STUDY OBJECTIVE: Emergency department (ED) visits for hypertension are rapidly increasing. Hypertension guidelines began recommending use of self-measurement blood pressure (BP) devices in the early 2000s, which could be contributing to the increase. We aim to examine the proportion of ED visits for hypertension that occurred after a BP measurement with a self-measuring device, and the associated outcomes. METHODS: This retrospective observational study included adults who made an ED visit and received a primary diagnosis of hypertension at 1 of 5 community and tertiary hospitals in Ontario, Canada, between April 2010 and March 2011. We categorized ED visits into 4 groups: those made after a home BP reading, a pharmacy reading, as a result of a physician referral, and all others (termed "not documented"). We examined rates of admission to the hospital, ED treatment (administration of antihypertensive medication and prescription provision), and post-ED clinical events (follow-up care, return ED visits, and long-term all-cause mortality) by group. RESULTS: Among 1,508 qualifying patients, median presenting ED BP was 182/97 mm Hg (interquartile range 164 to 200/85 to 109 mm Hg). The percentage of patients who presented to the ED after a reading at home, at a pharmacy, or by physician referral and the remaining patients not documented was 40.9%, 8.3%, 13.3%, and 37.5%, respectively. Overall, 109 patients (7.2%) were admitted to the hospital. The proportion of patients admitted after a home or pharmacy reading, after a physician referral, or who were not documented was 3.1%, 11.9%, and 11.0%, respectively. Two-year mortality rates were 5.4%, 0.0%, 6.5%, and 5.3% for the home, pharmacy, physician referral, and not documented groups, respectively. Among the 92.8% of patients who were discharged from the ED, 11% made another ED visit for hypertension within a year. CONCLUSION: In this study, half of patients with an ED visit that was primarily for hypertension presented after elevated readings on self-measurement devices. Only 3% of these patients were admitted to the hospital.


Asunto(s)
Atención Ambulatoria/estadística & datos numéricos , Determinación de la Presión Sanguínea/instrumentación , Hipertensión/diagnóstico , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Masculino , Ontario , Estudios Retrospectivos
7.
Virchows Arch ; 470(5): 505-515, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28315938

RESUMEN

Mast cells (MCs) are a part of the innate immune system. The MC functions toward cancer are partially based on the release of chymase and tryptase. However, the MC effect on breast cancer is controversial. The aim of our study was to investigate the presence of MCs in breast cancer tumors of different molecular subtypes and their relationships with other pathological prognostic factors. Tryptase- and chymase-positive mast cell densities were evaluated by immunohistochemistry in 108 primary invasive breast cancer tissue samples. Positive cells were counted within the tumor bed and at the invasive margin. For all analyzed MC subpopulations, we observed statistically significant differences between individual molecular subtypes of breast cancer. The significantly higher numbers of intratumoral chymase- and tryptase-positive mast cells were observed in luminal A and luminal B tumors compared to triple-negative and HER2+ non-luminal lesions. A denser MC infiltration was associated with lower tumor grade, higher ER and PR expression, lower proliferation rate as well as the lack of HER2 overexpression. The results obtained in our study indicate a possible association of chymase- and tryptase-positive MCs with more favorable cancer immunophenotype and with beneficial prognostic indicators in breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Mastocitos/patología , Microambiente Tumoral/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/genética , Neoplasias de la Mama/inmunología , Quimasas/análisis , Femenino , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Mastocitos/inmunología , Persona de Mediana Edad , Receptor ErbB-2/análisis , Receptor ErbB-2/biosíntesis , Receptor ErbB-2/genética , Receptores de Estrógenos/análisis , Receptores de Estrógenos/biosíntesis , Receptores de Estrógenos/genética , Receptores de Progesterona/análisis , Receptores de Progesterona/biosíntesis , Receptores de Progesterona/genética , Triptasas/análisis
8.
Micromachines (Basel) ; 8(7)2017 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-30400407

RESUMEN

A novel approach utilizing current feedback for the cytoplasmic microinjection of biological cells is proposed. In order to realize the cytoplasmic microinjection on small adherent cells (diameter < 30 µm and thickness < 10 µm), an electrical model is built and analyzed according to the electrochemical properties of target cells. In this study, we have verified the effectiveness of the current measurement for monitoring the injection process and the study of ion channel activities for verifying the cell viability of the cells after the microinjection.

9.
Appl Opt ; 54(21): 6558-65, 2015 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-26367843

RESUMEN

We present a comparative study of the bandwidth and the sensitivity of the resonance wavelength of long-period gratings (LPGs) to external perturbation fabricated in single-mode fibers (SMFs) and few-mode fibers (FMFs), and their dependencies on the group indices and the dispersion properties of the phase-matched modes. Unlike SMFs, a relatively large core size of FMFs invariably leads to nonuniform index modulation across the fiber cross section under UV exposure, enabling the coupling between modes having dissimilar azimuthal symmetry. Simple analytical formulas for the group/effective index difference, dispersion difference, bandwidth, and wavelength sensitivities are derived for the case of SMFs where light is coupled from the fundamental core mode to the symmetrical cladding modes. Our results show that a two-mode fiber operating at a V-number close to 3 is capable of producing LPGs with broader bandwidth and higher sensitivity as compared with their SMF counterparts, except for a few special cases. Our analyses provide insights into the characteristics of LPGs and facilitate their designs for specific applications.

10.
J Opt Soc Am A Opt Image Sci Vis ; 31(7): 1462-7, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25121432

RESUMEN

We investigate how the index profile of a few-mode fiber (FMF) can be designed so that group velocities of the two lowest-order modes can be equalized at a normalized frequency, which is below the cut-off frequency of the LP21 mode. This can be achieved using a single-clad power-law profile with a sufficiently large profile exponent or a double-clad profile consisting of a graded-core surrounded by a sufficiently thick depressed inner cladding without index jump at their interface. The fabrication tolerances, effective index differences, intramodal dispersion differences, and effective mode areas of various single- and double-clad profiles are compared. The results show that, in comparison to single-clad fibers, double-clad fibers are capable of producing higher fabrication tolerances and reduced sensitivity of group delay difference to wavelength by three and two orders of magnitude, respectively. Our analyses provide insights into the design of FMFs, which will facilitate future development of high-capacity mode division long-haul transmission systems.

11.
Opt Express ; 20(4): 4548-63, 2012 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-22418214

RESUMEN

The propagation dynamics of 7-core multi-core fibers (MCFs) with identical and three-types of cores are analytically derived based on the coupled-mode theory. The mode coupling dynamics can be aperiodic with transmission distance for MCF with identical cores. For MCFs with heterogeneous cores, it is found that even though signals from different core groups will not couple with each other, the coupling within their own group is significantly affected by the presence of other core groups. Joint signal processing techniques to mitigate mode coupling induced-cross-talks such as least mean square (LMS) algorithm and maximum likelihood (ML) detection are investigated and corresponding transmission performance are determined for coherent as well as intensity modulated formats. It is shown that aperiodic mode coupling in intensity modulated systems induces cross-talks that are difficult to eliminate through signal processing. The analytical insights may help in optimizing MCF designs and corresponding signal processing techniques for future high capacity MCF transmission systems.

12.
J Thorac Cardiovasc Surg ; 142(3): 595-601, 601.e1-2, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21247593

RESUMEN

OBJECTIVE: To assess the influence of gender on mortality after aortic valve replacement for aortic stenosis. METHODS: A retrospective analysis was performed on data prospectively collected from all patients undergoing aortic valve replacement for aortic stenosis. Multivariate regression analysis was performed to evaluate the effect of 22 preoperative and operative variables on early, late, and overall mortality. RESULTS: Aortic valve replacement was performed in 3343 patients with aortic stenosis between 1982 and 2003. The female patients were older, with a smaller body mass index. The women were less likely to have diabetes, chronic obstructive pulmonary disease, previous myocardial infarction, or left ventricular ejection fraction <35% but were more likely to have hypertension or a New York Heart Association III-IV classification. The female patients received a smaller prosthetic valve, with a smaller effective orifice area index (EOAI). The mean follow-up period was 6.18 ± 4.96 years, with a total of 2066.142 years of follow-up. The independent predictors of early mortality for the male patients included age, concomitant surgical revascularization, congestive heart failure, and valve size of ≤21 mm. The independent predictors of late mortality for the male patients included age, concomitant surgical revascularization, diabetes, renal failure, chronic obstructive pulmonary disease, congestive heart failure, and a bioprosthetic valve. The independent predictors of overall mortality for the male patients included age, concomitant surgical revascularization, diabetes, renal failure, heart failure, and valve size of ≤21 mm. For the female patients, the risk factors for early mortality included body mass index <25 kg/m(2); for late mortality included age, concomitant surgical revascularization, New York Heart Association class III-IV, and diabetes; and for overall mortality included age, concomitant surgical revascularization, New York Heart Association class III-IV, and renal failure. Furthermore, male gender was an independent predictor of late (but not early or overall) mortality. CONCLUSIONS: The independent predictors of mortality after aortic valve replacement for aortic stenosis differed between the male and female patients. Male gender increased the risk of late mortality, and a valve size of ≤21 mm increased the risk of early and overall mortality among the male patients only. These differences need to be taken into consideration preoperatively and require consideration during operative management.


Asunto(s)
Estenosis de la Válvula Aórtica/mortalidad , Estenosis de la Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Anciano , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/epidemiología , Bioprótesis , Índice de Masa Corporal , Femenino , Prótesis Valvulares Cardíacas , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Diseño de Prótesis , Estudios Retrospectivos , Factores Sexuales
13.
Ann Thorac Surg ; 89(1): 51-8; discussion 59, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20103205

RESUMEN

BACKGROUND: The effect of prosthesis-patient mismatch on long-term survival after aortic valve replacement has received considerable attention but there remains controversy. This study was performed to determine the predictors of mortality after aortic valve replacement and influence of prosthesis-patient mismatch on survival. METHODS: Contemporary mechanical prostheses and bioprostheses were implanted in 3,343 patients with aortic valve replacement between 1982 and 2003. The mean age was 68.06 +/- 11.20 years (median 70.06; range, 19 to 94), and the mean follow-up was 6.18 +/- 4.96 years, for a total of 20,666 years of follow-up. Prosthesis-patient mismatch was classified by effective orifice area index categories: normal (> 0.85 cm(2)/m(2)), 1,547 (46.3%); mild-to-moderate (> 0.65 cm(2)/m(2) to < or = 0.85 cm(2)/m(2)), 1,584 (47.4%); and severe (< 0.65 cm(2)/m(2)), 212 (6.3%). RESULTS: The predictors of overall mortality were age, age categorization, New York Heart Association functional class III/IV, concomitant coronary artery bypass graft surgery, prosthesis type, preoperative congestive heart failure, diabetes mellitus, renal failure, and chronic obstructive pulmonary disease. All categories of effective orifice area indexes were not predictive of overall mortality, late mortality, or early mortality. The 15-year overall survival was differentiated by effective orifice area index categories: 38.1% +/- 2.1%, 37.0% +/- 2.2%, and 22.1% +/- 6.5%, respectively, for the three categories. Survival adjusted for the covariates (effective orifice area index, age, basal mass index, and ejection fraction) determined no effect except severe effective orifice area index when adjusted for ejection fraction more than 50% (p = 0.049). CONCLUSIONS: Prosthesis-patient mismatch is not a predictor of overall standard unadjusted mortality to 15 years after aortic valve replacement, regardless of the category of effective orifice area index.


Asunto(s)
Válvula Aórtica/cirugía , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Prótesis Valvulares Cardíacas , Medición de Riesgo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Colombia Británica/epidemiología , Femenino , Estudios de Seguimiento , Enfermedades de las Válvulas Cardíacas/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Falla de Prótesis , Ajuste de Prótesis , Reoperación , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Factores de Tiempo , Adulto Joven
14.
Am J Med Sci ; 337(6): 432-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19525662

RESUMEN

BACKGROUND: Autoimmune thyroid disease (AITD) often coexists with pernicious anemia (PA) among whites. The study aimed to determine thyroid autoimmunity in Chinese patients with PA. METHODS: From the data of a hospital-based longitudinal study of Chinese PA patients (1994-2007), those with complete information of antibodies to thyroid peroxidase (TPO), thyroglobulin (Tg), and gastric parietal cell; serum thyroid-stimulating hormone and free thyroxine; gastric mucosal histology; and family history of AITD were analyzed. RESULTS: Among 126 Chinese PA patients, 44% had TPO/Tg antibodies and 13.5% AITD. TPO/Tg antibodies occurred in 33% (16 of 49) of male and 52% (40 of 77) of female patients (P = 0.034). Graves disease (8 patients) tended to antedate PA and was associated with no or low titers of TPO/Tg antibodies. Primary hypothyroidism (9 patients) developed during follow-up and was associated with high TPO/Tg antibody titers. The TPO/Tg antibodies did not affect the clinical course of PA but was associated with an enhanced risk of developing AITD and vitiligo. Overall, AITD (before and after PA) occurred in 23% (13 of 56) and 5.7% (4 of 70) of PA patients with and without antibodies (P = 004). During follow-up (mean duration of 75.24 +/- 46.39 months), 10 patients developed AITD-7 new onset of hypothyroidism and 3 progression/relapse of prior AITD. Logistic regression analysis of presenting features of PA revealed 2 independent factors for AITD development during follow-up-presence of thyroid antibodies (odds ratio 20.2, 95% confidence interval 1.8-223) and history of prior AITD (odds ratio 39.8, 95% confidence interval 2.3-679). CONCLUSION: It is recommended to screen thyroid antibodies and monitor thyroid function during follow-up.


Asunto(s)
Anemia Perniciosa/complicaciones , Tiroiditis Autoinmune/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Autoanticuerpos/sangre , China , Femenino , Humanos , Masculino , Persona de Mediana Edad
15.
J Thorac Cardiovasc Surg ; 137(5): 1109-15.e2, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19379975

RESUMEN

OBJECTIVE: The Artificial Valve Endocarditis Reduction Trial was stopped on January 21, 2000, due to a higher incidence of paraprosthetic leak in the St Jude Medical Silzone prosthesis compared with the conventional prosthesis. The Artificial Valve Endocarditis Reduction Trial investigators reported the 2-year results in 2002. This retrospective study assessed the influence on thromboembolism and paraprosthetic leak to 7 years. METHODS: A total of 253 patients had 254 operations: 80 aortic valve replacements, 139 mitral valve replacements, and 35 multiple replacements with placement of Silzone prostheses. The mean age was 58.6 years (range 21-84 years, median age 59.8 years), and there were 126 women (49.8%) and 74 concomitant procedures (coronary artery bypass 28.9%). RESULTS: Major paraprosthetic leak (repair, re-replacement, or mortality) occurred in 10 of the original procedures after 30 days (3 aortic valve replacements, 3 mitral valve replacements, 4 multiple replacements). Nine occurrences in 8 patients-5 early (2 years)-were managed. Seven were managed with definitive re-replacement. One was an early nonoperative fatality. There was 1 late fatality after the second late paraprosthetic leak reoperation. One of the 10 procedures occurring after 2 years had mild to moderate aortic valve replacement paraprosthetic leak managed as an incidental re-replacement at the time of correction of supra valvular patch stenosis. One additional occurrence, in addition to the 8 patients (<30 days), was considered a technical error and not related to the Silzone prosthesis and was replaced with a Silzone prosthesis. The linearized rate of paraprosthetic leak within the first 2 years of follow-up was 1.3%/patient-year and after 2 years was 0.4%/patient-year. The linearized occurrence rate for major thromboembolism was 0.42%/patient-year for aortic valve replacement and 1.71%/patient-year for mitral valve replacement. CONCLUSIONS: Paraprosthetic leak with the St Jude Medical Silzone prosthesis was managed both during the early (2years) intervals with re-replacement. Late managed events may be manifestations of earlier occurring paraprosthetic leak. Follow-up echocardiograms should meet standards of care, 6 to 12 months after surgery and at the slightest suspicion of dysfunction. There is no advanced continuing risk of the St Jude Medical Silzone prosthesis.


Asunto(s)
Bioprótesis , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Prótesis Valvulares Cardíacas , Falla de Prótesis , Infecciones Relacionadas con Prótesis/epidemiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Válvula Aórtica/cirugía , Estudios de Cohortes , Intervalos de Confianza , Femenino , Estudios de Seguimiento , Enfermedades de las Válvulas Cardíacas/diagnóstico , Enfermedades de las Válvulas Cardíacas/mortalidad , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Válvula Mitral/cirugía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Probabilidad , Diseño de Prótesis , Infecciones Relacionadas con Prótesis/diagnóstico , Estudios Retrospectivos , Medición de Riesgo , Distribución por Sexo , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
16.
J Opt Soc Am A Opt Image Sci Vis ; 26(3): 489-96, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19252647

RESUMEN

We demonstrate a Bragg-reflection grating coupler using a nonlinear dual-core fiber with a long-period grating (LPG) and a fiber Bragg grating (FBG) inscribed in different cores. The LPG couples light from the primary core to the cladding, while the FBG operating in reflection acts to drop the channel from the secondary core. The coupler is nonreflective along the launching core. Theoretical analysis of this structure demonstrates a design for obtaining a flat-top bandpass filter with high reflectivity, steep band transitions, and negligible sidelobes. By launching an intense pump beam into the individual cores, a switchable and a wavelength tunable passband can be achieved. The results demonstrate the usefulness of the device as a grating-based all-optical element.

17.
Ann Thorac Surg ; 87(4): 1135-41; discussion 1142, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19324139

RESUMEN

BACKGROUND: The effect of prosthesis-patient mismatch on long-term survival after mitral valve replacement (MVR) has received limited attention. This study was performed to determine the predictors of mortality after MVR and influence of prosthesis-patient mismatch on survival. METHODS: Contemporary mechanical prostheses and bioprostheses were implanted in 2,440 patients with MVR between 1982 and 2002. The mean age was 63.9 +/- 12.1 years and the mean follow-up was 6.1 +/- 4.6 years, a total of 14,797.7 years of follow-up. Prosthesis-patient mismatch was classified by effective orifice area index categories: normal, greater than 1.2 cm(2)/m(2) (345, 14.2%); mild-to-moderate, equal to or less than 1.2 to greater than 0.9 cm(2)/m(2) (1,696, 69.5%); and severe, equal to or less than 0.9 cm(2)/m(2) (399, 16.4%). RESULTS: The predictors of overall mortality were age, age categorization, New York Heart Association III-IV, concomitant coronary artery bypass, ventricular dysfunction, prosthesis type, body mass index, and pulmonary hypertension. All categories of effective orifice area indices (EOAIs) were not predictive of overall mortality, late mortality, or early mortality. The 15-year survival was not differentiated by EOAI categories; 32.0 +/- 4.4%, 32.9 +/- 2.1%, and 36.6 +/- 6.3%, respectively, for the three categories. Pulmonary hypertension influenced mortality by EOAI categories; normal versus mild-to-moderate (p = 0.0317) and normal versus severe (p = 0.0320). The EOAI was not an independent predictor of mortality in the consideration of patients with pulmonary hypertension but there is an interaction between pulmonary hypertension and mild-to-moderate (p = 0.023) and severe (p = 0.031) EOAI. CONCLUSION: Prosthesis-patient mismatch is not a predictor of overall mortality to 15 years after MVR regardless of the category of effective orifice area index. The preoperative variable, pulmonary hypertension, influences overall mortality in the presence of mild-to-moderate and severe prosthesis-patient mismatch in the survival analysis.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Prótesis Valvulares Cardíacas , Válvula Mitral/cirugía , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Falla de Prótesis , Ajuste de Prótesis , Estudios Retrospectivos , Análisis de Supervivencia
19.
Opt Lett ; 32(23): 3376-8, 2007 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-18059938

RESUMEN

We demonstrate a grating coupler using an asymmetric nonlinear dual-core fiber with a pair of long-period gratings (LPGs). Simple formulas for the achievement of 100% coupling efficiency and small sidelobes are derived. The passband exhibits steep band transitions. By launching high-intensity optical pumps to alter the refractive indices of the fiber cores through cross-phase modulation, a wavelength tunable LPG dual-core coupler can be realized.

20.
Mol Cancer Ther ; 6(12 Pt 1): 3147-57, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18089709

RESUMEN

The Aurora family of serine/threonine kinases is important for the regulation of centrosome maturation, chromosome segregation, and cytokinesis during mitosis. Overexpression of Aurora kinases in mammalian cells leads to genetic instability and transformation. Increased levels of Aurora kinases have also been linked to a broad range of human tumors. Here, we describe the properties of CCT129202, a representative of a structurally novel series of imidazopyridine small-molecule inhibitors of Aurora kinase activity. This compound showed high selectivity for the Aurora kinases over a panel of other kinases tested and inhibits proliferation in multiple cultured human tumor cell lines. CCT129202 causes the accumulation of human tumor cells with >or=4N DNA content, leading to apoptosis. CCT120202-treated human tumor cells showed a delay in mitosis, abrogation of nocodazole-induced mitotic arrest, and spindle defects. Growth of HCT116 xenografts in nude mice was inhibited after i.p. administration of CCT129202. We show that p21, the cyclin-dependent kinase inhibitor, is induced by CCT129202. Up-regulation of p21 by CCT129202 in HCT116 cells led to Rb hypophosphorylation and E2F inhibition, contributing to a decrease in thymidine kinase 1 transcription. This has facilitated the use of 3'-deoxy-3'[(18)F]fluorothymidine-positron emission tomography to measure noninvasively the biological activity of the Aurora kinase inhibitor CCT129202 in vivo.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Imidazoles/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Piridinas/farmacología , Animales , Apoptosis/efectos de los fármacos , Aurora Quinasas , Línea Celular Tumoral , Regulación hacia Abajo , Inhibidores Enzimáticos/farmacocinética , Ensayo de Inmunoadsorción Enzimática , Femenino , Histonas/metabolismo , Humanos , Ratones , Microscopía Fluorescente , Mitosis/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosforilación , Proteína de Retinoblastoma/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
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