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1.
BMC Infect Dis ; 24(1): 871, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39223456

RESUMEN

BACKGROUND: During the pandemic period, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutated, leading to changes in the disease's severity and the therapeutic effect of drugs accordingly. This study aimed to present the actual use of therapeutics and clinical outcomes based on the prevalence of each variant using real-world data. METHODS: We analyzed the electronic medical records of adult patients admitted to Busan Medical Center after confirming coronavirus disease 2019 (COVID-19) from February 1, 2020, to June 30, 2022. Patients with mild-to-moderate COVID-19 who were at a high risk of disease progression were selected as study subjects, and the time period was classified according to the variants as ancestral strain, Delta variant, or Omicron variant. We compared drug use status and clinical outcomes by time period. RESULTS: Among all 3,091 patients, corticosteroids were the most commonly used therapy (56.0%), being used most frequently in the Delta variant (93.0%), followed by the Omicron variant (42.9%) and ancestral strain (21.2%). Regdanvimab accounted for the majority of therapeutic use in the Delta variant (82.9%) and ancestral strain (76.8%), whereas remdesivir was most frequently used during the Omicron variant period (68.9%). The composite outcomes of death or disease aggravation were ranked in the order of the Delta variant, Omicron variant, and ancestral strain (14.5, 11.9, and 6.0%, respectively, P < 0.001). CONCLUSION: Regdanvimab was primarily used during the ancestral strain period, regdanvimab plus corticosteroids during the Delta variant period, and remdesivir during the Omicron variant period. The rate of death or disease aggravation was highest in the Delta variant, followed by the Omicron variant and the ancestral strain.


Asunto(s)
Antivirales , Tratamiento Farmacológico de COVID-19 , COVID-19 , Mutación , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/efectos de los fármacos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Antivirales/uso terapéutico , COVID-19/virología , COVID-19/epidemiología , COVID-19/mortalidad , Adulto , Anciano , Resultado del Tratamiento , Índice de Severidad de la Enfermedad , Corticoesteroides/uso terapéutico , Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados
2.
Opt Express ; 32(3): 3278-3289, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297553

RESUMEN

Quantum well intermixing (QWI) is an effective method for simple and well-defined monolithic integration of photonic devices. We introduce an identical-active electro-absorption modulated laser (IA-EML) with optimized QWI, which is applied to reduce the absorptive waveguide region. To determine the optimal intermixed IA-EML structure, we conduct a comparative analysis between the cases of an IA-EML with only an intermixed waveguide region and with both intermixed waveguide and electro-absorption modulator (EAM) regions, as well as the case without QWI. The results reveal that the intermixed region effectively inhibits the absorption in the waveguide. In particular, the IA-EML with only waveguide intermixing exhibits superior modulation characteristics with low driving voltages and a high extinction ratio. Our work provides an attractive approach for suppressing the absorptive waveguide region in the IA-EML to enhance modulation performance and to develop photonic integrated circuits with a simplified process.

3.
J Korean Acad Nurs ; 53(2): 249-259, 2023 Apr.
Artículo en Coreano | MEDLINE | ID: mdl-37164351

RESUMEN

PURPOSE: Based on the Reserve Capacity Model, this study investigated the effects of pre- and postmenopausal women's socioeconomic status (SES) on depression, focusing on the mediating effects of self-esteem, happiness, and family relationship satisfaction with social network relationships. METHODS: This cross-sectional study involved secondary analysis of national data on 771 perimenopause women gathered from the 16th Korea Welfare Panel Study (KOWEPS) 2021. A path analysis model was constructed to evaluate the relationship between SES, social network satisfaction, self-esteem, perceived health status, and depression. Data were analyzed using ADANCO 2.3.1 and Mplus 8.4. RESULTS: Although SES had no direct effect on depression, it did affect depression through self-esteem, happiness, and satisfaction with family relationships. CONCLUSION: The findings of this study indicate that perimenopausal women's personal resources-psychosocial variables such as self-esteem and happiness-had a higher effect on depression than tangible reserves like SES. Therefore, interventions for enhancing self-esteem and happiness may prevent depression in perimenopausal women effectively.


Asunto(s)
Perimenopausia , Clase Social , Humanos , Femenino , Estudios Transversales , Estado de Salud , Satisfacción Personal
4.
Biomater Sci ; 10(21): 6160-6171, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36222413

RESUMEN

Compared to normal cells, cancer cells are more susceptible to insults of prooxidants that generate ROS (reactive oxygen species) or scavenge antioxidants such as glutathione (GSH). Cancer cells undergo immunogenic cell death (ICD) by elevated oxidative stress. Herein, we report rationally designed F-ssPBCA nanoparticles as a tumor-targeting prooxidant, which generates ROS and scavenges GSH simultaneously to cooperatively amplify oxidative stress, leading to ICD. Prooxidant F-ssPBCA nanoparticles are composed of a disulfide-bridged GSH scavenging dimeric prodrug (ssPB) that self-assembles to form nanoconstructs and encapsulates ROS-generating BCA (benzoyloxy cinnamaldehyde). F-ssPBCA nanoparticles significantly elevate oxidative stress to kill cancer cells and also evoke ICD featured by the release of CRT (calreticulin), HMGB-1 (high mobility group box-1), and adenosine triphosphate (ATP). Animal studies revealed that F-ssPBCA nanoparticles accumulate in tumors preferentially and suppress tumor growth effectively. The results of this study demonstrate that prooxidant-mediated oxidative stress elevation is a highly effective strategy to kill cancer cells selectively and even evoke abundant ICD. We anticipate that oxidative stress amplifying F-ssPBCA nanoparticles hold tremendous translational potential as a tumor targeted ICD-inducing anticancer nanomedicine.


Asunto(s)
Antineoplásicos , Nanopartículas , Neoplasias , Profármacos , Animales , Especies Reactivas de Oxígeno/metabolismo , Calreticulina/farmacología , Antioxidantes/farmacología , Profármacos/farmacología , Nanomedicina , Antineoplásicos/farmacología , Estrés Oxidativo , Neoplasias/tratamiento farmacológico , Glutatión/metabolismo , Disulfuros/metabolismo , Adenosina Trifosfato/metabolismo , Proteínas HMGB/metabolismo , Proteínas HMGB/farmacología , Línea Celular Tumoral
5.
J Korean Med Sci ; 37(13): e102, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35380027

RESUMEN

BACKGROUND: Regdanvimab has decreased the time to clinical recovery from coronavirus disease 2019 (COVID-19) and lowered the rate of oxygen therapy according to the results from phase 2/3 randomized controlled trial. More information is needed about the effects and safety of regdanvimab. METHODS: We analyzed data for patients with high-risk mild or moderate COVID-19 being admitted to Busan Medical Center between December 1, 2020 and April 16, 2021. A propensity score (PS) matched analysis was conducted to compare patients treated with and without regdanvimab. The primary outcome was in-hospital death or disease aggravation which means the need for oxygen therapy (low- or high-flow oxygen therapy and mechanical ventilation) and secondary outcomes comprised the length of hospital stay and adverse reactions. RESULTS: Among 1,617 selected patients, 970 (60.0%) were indicated for regdanvimab. Of these, 377 (38.9%) were administered with regdanvimab. Among a 1:1 PS-matched cohort of 377 patients each treated with and without regdanvimab, 19 (5%) and 81 (21.5%) reached the composite outcome of death, or disease aggravation, respectively (absolute risk difference, -16.4%; 95% confidence interval [CI], -21.1, -11.7; relative risk difference, 76.5%; P < 0.001). Regdanvimab significantly reduced the composite outcome of death, or disease aggravation in univariate (odds ratio [OR], 0.194; 95% CI, 0.112-0.320; P < 0.001) and multivariable-adjusted analyses (OR, 0.169; 95% CI, 0.095-0.289; P < 0.001). The hospital stay was shorter for the group with than without regdanvimab. Some hematological adverse reactions were more frequent in the group without regdanvimab, but other adverse reactions did not significantly differ between the groups. CONCLUSION: Regdanvimab was associated with a significantly lower risk of disease aggravation without increasing adverse reactions.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Anticuerpos Neutralizantes , Tratamiento Farmacológico de COVID-19 , Inmunoglobulina G , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Neutralizantes/efectos adversos , Mortalidad Hospitalaria , Humanos , Inmunoglobulina G/efectos adversos , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
6.
Medicina (Kaunas) ; 57(10)2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34684165

RESUMEN

Background and objectives: Blood vessel thrombosis causes blood circulation disorders, leading to various diseases. Currently, various antiplatelet and anticoagulant drugs, such as aspirin, warfarin, heparin, and non-vitamin K antagonist oral anticoagulants (NOACs), are used as the major drugs for the treatment of a wide range of thrombosis. However, these drugs have a side effect of possibly causing internal bleeding due to poor hemostasis when taken for a long period of time. Materials and Methods: Gastrodia elata Blume (GE) and Zanthoxylum schinifolium Siebold & Zucc (ZS) are known to exhibit hemostatic and antiplatelet effects as traditional medicines that have been used for a long time. In this study, we investigated the effect of a mixed extract of GE and ZS (MJGE09) on platelet aggregation and plasma coagulation. Results: We found that MJGE09 inhibited collagen-and ADP-induced platelet aggregation in vitro. In addition, collagen- and ADP-induced platelet aggregation were also inhibited in a dose-dependent manner on the platelets of mice that were orally administered MJGE09 ex vivo. However, compared with aspirin, MJGE09 did not prolong the rat tail vein bleeding time in vivo and did not show a significant effect on the increase in the prothrombin time (PT) and activated partial thromboplastin time (aPTT). Conclusions: These results suggest that MJGE09 can be used as a potential anticoagulant with improved antithrombotic efficacy.


Asunto(s)
Gastrodia , Trombosis , Zanthoxylum , Administración Oral , Animales , Anticoagulantes/farmacología , Anticoagulantes/uso terapéutico , Fibrinolíticos/uso terapéutico , Ratones , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Agregación Plaquetaria , Inhibidores de Agregación Plaquetaria/farmacología , Ratas , Ratas Sprague-Dawley , Trombosis/tratamiento farmacológico
7.
Nanomaterials (Basel) ; 11(10)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34685012

RESUMEN

Ultrasound is clinically used for diagnosis and interventions for musculoskeletal injuries like muscle contusion, but contrast of ultrasonography still remains a challenge in the field of the musculoskeletal system. A level of hydrogen peroxide (H2O2) is known to be elevated during mechanical tissue damage and therefore H2O2 can be exploited as a diagnostic and therapeutic marker for mechanical injuries in the musculoskeletal system. We previously developed poly(vanillin-oxalate) (PVO) as an inflammation-responsive polymeric prodrug of vanillin, which is designed to rapidly respond to H2O2 and exert antioxidant and anti-inflammatory activities. The primary aim of this study is to verify whether PVO nanoparticles could serve as contrast agents as well as therapeutic agents for musculoskeletal injuries simultaneously. In a rat model of contusion-induced muscle injury, PVO nanoparticles generated CO2 bubbles to enhance the ultrasound contrast in the injury site. A single intramuscular injection of PVO nanoparticles also suppressed contusion-induced muscle damages by inhibiting the expression of pro-inflammatory cytokines and inflammatory cell infiltration. We, therefore, anticipate that PVO nanoparticles have great translational potential as not only ultrasound imaging agents but also therapeutic agents for the musculoskeletal disorders such as contusion.

8.
Biomacromolecules ; 22(5): 2043-2056, 2021 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-33835793

RESUMEN

Despite widespread interest in the amphiphilic polymeric micelles for drug delivery systems, it is highly desirable to achieve high loading capacity and high efficiency to reduce the side effects of therapeutic agents while maximizing their efficacy. Here, we present a novel hydrophobic epoxide monomer, cyclohexyloxy ethyl glycidyl ether (CHGE), containing an acetal group as a pH-responsive cleavable linkage. A series of its homopolymers, poly(cyclohexyloxy ethyl glycidyl ether)s (PCHGEs), and block copolymers, poly(ethylene glycol)-block-poly(cyclohexyloxy ethyl glycidyl ether)s (mPEG-b-PCHGE), were synthesized via anionic ring-opening polymerization in a controlled manner. Subsequently, the self-assembled polymeric micelles of mPEG-b-PCHGE demonstrated high loading capacity, excellent stability in biological media, tunable release efficiency, and high cell viability. Importantly, quantum mechanical calculations performed by considering prolonged hydrolysis of the acetal group in CHGE indicated that the CHGE monomer had higher hydrophobicity than three other functional epoxide monomer analogues developed. Furthermore, the preferential cellular uptake and in vivo therapeutic efficacy confirmed the enhanced stability and the pH-responsive degradation of the amphiphilic block copolymer micelles. This study provides a new platform for the development of versatile smart polymeric drug delivery systems with high loading efficiency and tailorable release profiles.


Asunto(s)
Sistemas de Liberación de Medicamentos , Micelas , Portadores de Fármacos , Concentración de Iones de Hidrógeno , Polietilenglicoles , Polimerizacion , Polímeros
9.
J Korean Med Sci ; 36(10): e71, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33724738

RESUMEN

BACKGROUND: For the 2018-2019 season, the national influenza immunization program expanded to cover children aged from 6 months to 12 years in Korea. This study aimed to analyze vaccine effectiveness (VE) against influenza in children visiting the pediatric emergency room at a tertiary hospital during the 2018-2019 season. METHODS: Patients tested for influenza antigens from October 1st 2018 to May 31st 2019 at the pediatric emergency room of Samsung Medical Center were included. Patients' influenza antigen test results, influenza vaccination history, and underlying medical conditions were reviewed retrospectively. VE was estimated from the test-negative design study. RESULTS: Among the 2,901 visits with influenza test results 1,692 visits of 1,417 patients were included for analysis. Among these 1,417 patients, 285 (20.1%) were positive (influenza A, n = 211, 74.0%; influenza B, n = 74, 26.0%). The VE in all patients was 36.4% (95% confidence interval [CI], 13.9 to 53.1). The VE for influenza A was 37.6% (95% CI, 12.6 to 55.5) and VE for influenza B was 24.0% (?38.5 to 58.3). The VE in the age group 6 months to 12 years was significant with a value of 35.6% (95% CI, 10.5 to 53.7); it was not statistically significant in the age group 13 to 18 years. In a multivariate logistic regression model, patients who received an influenza vaccination were less likely to get influenza infection (OR, 0.6; 95% CI, 0.4 to 0.8; P = 0.001), with significant confounding factors such as age group 13 to 18 years (OR, 0.5; 95% CI, 0.3 to 0.8; P = 0.003) and underlying hematology-oncology disease (OR, 0.3; 95% CI, 0.1 to 0.6; P = 0.002). CONCLUSION: We report moderate effectiveness of influenza vaccination in previously healthy children aged from 6 months to 12 years in the 2018-2019 season.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Programas de Inmunización/organización & administración , Vacunas contra la Influenza/uso terapéutico , Gripe Humana/prevención & control , Vacunación/estadística & datos numéricos , Adolescente , Niño , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/epidemiología , Gripe Humana/virología , Masculino , República de Corea/epidemiología , Estudios Retrospectivos , Estaciones del Año
10.
Virus Evol ; 7(1): veaa105, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35186322

RESUMEN

When emerging pathogens encounter new host species for which they are poorly adapted, they must evolve to escape extinction. Pathogens experience selection on traits at multiple scales, including replication rates within host individuals and transmissibility between hosts. We analyze a stochastic model linking pathogen growth and competition within individuals to transmission between individuals. Our analysis reveals a new factor, the cross-scale reproductive number of a mutant virion, that quantifies how quickly mutant strains increase in frequency when they initially appear in the infected host population. This cross-scale reproductive number combines with viral mutation rates, single-strain reproductive numbers, and transmission bottleneck width to determine the likelihood of evolutionary emergence, and whether evolution occurs swiftly or gradually within chains of transmission. We find that wider transmission bottlenecks facilitate emergence of pathogens with short-term infections, but hinder emergence of pathogens exhibiting cross-scale selective conflict and long-term infections. Our results provide a framework to advance the integration of laboratory, clinical, and field data in the context of evolutionary theory, laying the foundation for a new generation of evidence-based risk assessment of emergence threats.

11.
ACS Appl Bio Mater ; 4(5): 4450-4461, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35006857

RESUMEN

Phototherapy including photothermal therapy (PTT) and photodynamic therapy (PDT) uses photosensitizers and light to kill cancer cells and has become a promising therapeutic modality because of advantages such as minimal invasiveness and high cancer selectivity. However, PTT or PDT as a single treatment modality has insufficient therapeutic efficacy. Moreover, oxygen consumption by PDT activates angiogenic factors and leads to cancer recurrence and progression. Therefore, the therapeutic outcomes of phototherapy would be maximized by employing photosensitizers for concurrent PTT and PDT and suppressing angiogenic factors. Therefore, integrating photosensitive agents and antiangiogenic agents in a single nanoplatform would be a promising strategy to maximize the therapeutic efficacy of phototherapy. In this study, we developed hyaluronic acid-coated fluorescent boronated polysaccharide (HA-FBM) nanoparticles as a combination therapeutic agent for phototherapy and antiangiogenic therapy. Upon a single near-infrared laser irradiation, HA-FBM nanoparticles generated heat and singlet oxygen simultaneously to kill cancer cells and also induced immunogenic cancer cell death. Beside their fundamental roles as photosensitizers, HA-FBM nanoparticles exerted antiangiogenic effects by suppressing the vascular endothelial growth factor (VEGF) and cancer cell migration. In a mouse xenograft model, intravenously injected HA-FBM nanoparticles targeted tumors by binding CD44-overexpressing cancer cells and suppressed angiogenic VEGF expression. Upon laser irradiation, HA-FBM nanoparticles remarkably eradicated tumors and increased anticancer immunity. Given their synergistic effects of phototherapy and antiangiogenic therapy from tumor-targeting HA-FBM nanoparticles, we believe that integrating the photosensitizers and antiangiogenic agents into a single nanoplatform presents an attractive strategy to maximize the anticancer therapeutic efficacy of phototherapy.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Antineoplásicos/farmacología , Materiales Biocompatibles/farmacología , Peróxido de Hidrógeno/metabolismo , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Inhibidores de la Angiogénesis/síntesis química , Inhibidores de la Angiogénesis/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Rayos Láser , Ensayo de Materiales , Ratones , Estructura Molecular , Nanopartículas/química , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Imagen Óptica , Tamaño de la Partícula , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/química , Polisacáridos/química , Polisacáridos/farmacología , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/metabolismo
12.
ACS Appl Mater Interfaces ; 11(17): 15201-15211, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30945843

RESUMEN

Daily treatment of diabetes to stabilize blood glucose level poses a challenge for patients with diabetes mellitus. Diabetes is a long-term metabolic disorder, and the treatment lasts for the rest of the patient's life after diagnosis. We presented a new injectable hydrogel depot system using exendin 4 (Ex-4) interactive and complex forming polymeric ionic-nano-particles for long-term antidiabetes treatment. Protamine-conjugated polymer (ProCP) was developed to form ionic-nano-complexes with Ex-4, as the amino-group-rich protamine and the negatively charged Ex-4 ( pI: 4.86) interact with each other due to their opposite electric charges in physiological conditions. Morphologically, the ProCP were nanoparticles in aqueous condition (10 wt % of ProCP in phosphate-buffered solution, <25 °C) and formed condensed ionic- and nano-complexes with Ex-4. The complexes formed a bulk hydrogel when exposed to body temperature. A slow release of the Ex-4/ProCP ionic-nano-complexes occurred from the hydrogel depot, followed by Ex-4 dissociation from the ionic-nano-complexes and hydrolysis of ProCP. Given that the Ex-4 release occurs after the complex releases from the hydrogel, the periods of Ex-4 release and hydrogel maintenance may be similar. The present system showed a considerably prolonged Ex-4 release. Additionally, it showed potential as a long-term effective and reproducible antidiabetes treatment.


Asunto(s)
Exenatida/química , Hidrogeles/química , Hipoglucemiantes/química , Nanoestructuras/química , Polímeros/química , Animales , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/veterinaria , Exenatida/farmacocinética , Exenatida/uso terapéutico , Semivida , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/uso terapéutico , Inyecciones Subcutáneas , Iones/química , Masculino , Ratones , Ratones Desnudos , Células 3T3 NIH , Imagen Óptica , Polímeros/toxicidad , Protaminas/química , Ratas , Ratas Sprague-Dawley
13.
Sci Rep ; 9(1): 1346, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30718707

RESUMEN

This paper presents, for the first time, a study to analyze the surface morphology of metal extracted from a high temperature molten salt medium in the electrodeposit using x-ray radiography and computed tomography. Widely used methods such as scanning electron microscopy and inductively coupled plasma-optical emission spectrometry/mass spectrometry are destructive and the related processes are often subject to the air condition. The x-ray imaging can provide rich information of the target sample in a non-destructive way without invoking hydrolysis or oxidation of a hygroscopic sample. In this study, the x-ray imaging conditions were optimized as following: tube voltage at 100 kVp and the current exposure time product at 8.8 mAs in our in-house x-ray imaging system. LiCl-KCl and cerium metals used in this work produced substantially distinguishable contrasts in the radiography due to their distinctive attenuation characteristics, and this difference was well quantified in the histograms of brightness. Electrodeposits obtained by chronoamperometry and chronopotentiometry demonstrated a completely different behavior of electrodeposition even at the same applied charge. In particular, computed tomography and volumetric analysis clearly showed the structural and morphological dissimilarity. The structure of cerium metal in the electrodeposit was successfully separated from the chloride salt structure in the CT image by an image segmentation process.

14.
Med Phys ; 46(3): 1182-1197, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30592313

RESUMEN

PURPOSE: Scatter contamination constitutes a dominant source of degradation of image quality in cone-beam computed tomography (CBCT). We have recently developed an analytic image reconstruction method with a scatter correction capability from the partially blocked cone-beam data out of a single scan. Despite its easy implementation and its computational efficiency, the developed method may result in additional image artifacts for a large cone angle geometry due to data inconsistency. To improve the image quality at a large cone angle, we propose a weighted rebinned backprojection-filtration (wrBPF) algorithm in conjunction with a hybrid type scatter correction approach. METHODS: The proposed method uses a beam-blocker array that provides partial data for scatter correction and image reconstruction and that only blocks the beam within a limited cone angle. This design allows a chance to keep the image quality at larger cone angles by use of data redundancy since the projection data corresponding to larger cone angles are not blocked. However, the scatter correction would not be straightforward. In order to correct for the scatter in the projections at larger cone angles, we propose a novel scatter correction method combining a measurement-based and a convolution-based method. We first estimated the scatter signal using a measurement-based method in the partially beam-blocked regions, and then optimized the fitting parameters of a convolution-kernel that can be used for scatter correction in the projections at larger cone angles. For image reconstruction, we developed a wrBPF with butterfly filtering. We have conducted an experimental study to validate the proposed algorithm for image reconstruction and scatter correction. RESULTS: The experimental results revealed that the developed reconstruction method makes full use of the benefits of partial beam-blocking for scatter correction and image reconstruction and at the same time enhances image quality at larger cone angles by use of an optimized convolution-based scatter correction. CONCLUSIONS: The proposed method that enjoys the advantages of both measurement-based and convolution-based methods for scatter correction has successfully demonstrated its capability of reconstructing accurate images out of a single scan in circular CBCT.


Asunto(s)
Algoritmos , Tomografía Computarizada de Haz Cónico/métodos , Cabeza/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Artefactos , Simulación por Computador , Tomografía Computarizada de Haz Cónico/instrumentación , Humanos , Dispersión de Radiación
15.
J Natl Compr Canc Netw ; 16(7): 829-837, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30006425

RESUMEN

Background: The objective of this study was to examine the presence and magnitude of US geographic variation in use rates of both recommended and high-cost imaging in young patients with early-stage breast cancer during the 18 month period after surgical treatment of their primary tumor. Methods: Using the Truven Health MarketScan Commercial Database, a descriptive analysis was conducted of geographic variation in annual rates of dedicated breast imaging and high-cost body imaging of 36,045 women aged 18 to 64 years treated with surgery for invasive unilateral breast cancer between 2010 and 2012. Multivariate hierarchical analysis examined the relationship between likelihood of imaging and patient characteristics, with metropolitan statistical area (MSA) serving as a random effect. Patient characteristics included age group, BRCA1/2 carrier status, family history of breast cancer, combination of breast surgery type and radiation therapy, drug therapy, and payer type. All MSAs in the United States were included, with areas outside MSAs within a given state aggregated into a single area for analytic purposes. Results: Descriptive analysis of rates of imaging use and intensity within MSA regions revealed wide geographic variation, irrespective of treatment cohort or age group. Increased probability of recommended postoperative dedicated breast imaging was primarily associated with age and treatment including both surgery and radiation therapy, followed by MSA region (odds ratio, 1.42). Increased probability of PET use-a high-cost imaging modality for which postoperative routine use is not recommended in the absence of specific clinical findings-was primarily associated with surgery type followed by MSA region (odds ratio, 1.82). Conclusions: In patients with breast cancer treated for low-risk disease, geography has effects on the rates of posttreatment imaging, suggesting that some patients are not receiving beneficial dedicated breast imaging, and high-cost nonbreast imaging may not be targeted to those groups most likely to benefit.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Diagnóstico por Imagen/estadística & datos numéricos , Utilización de Instalaciones y Servicios/estadística & datos numéricos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasias Primarias Secundarias/diagnóstico por imagen , Cuidados Posoperatorios/estadística & datos numéricos , Adulto , Antineoplásicos Hormonales/uso terapéutico , Mama/diagnóstico por imagen , Mama/patología , Mama/cirugía , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Quimioradioterapia Adyuvante/normas , Bases de Datos Factuales/estadística & datos numéricos , Diagnóstico por Imagen/economía , Diagnóstico por Imagen/métodos , Utilización de Instalaciones y Servicios/economía , Femenino , Geografía , Humanos , Mastectomía , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/terapia , Estadificación de Neoplasias , Neoplasias Primarias Secundarias/patología , Neoplasias Primarias Secundarias/terapia , Cuidados Posoperatorios/economía , Cuidados Posoperatorios/normas , Guías de Práctica Clínica como Asunto , Radioterapia Adyuvante/estadística & datos numéricos , Estudios Retrospectivos , Estados Unidos , Adulto Joven
16.
Am J Clin Oncol ; 41(11): 1037-1042, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32463216

RESUMEN

OBJECTIVES: To examine the association between geography and utilization rates of contralateral prophylactic mastectomy (CPM) relative to patient-level factors in patients with early stage breast cancer. MATERIALS AND METHODS: Using the Truven Health MarketScan Commercial Database, a descriptive analysis of geographic variation in genetic testing and CPM rates of 38,108 women ages 18 to 64 years treated with surgery for invasive unilateral breast cancer between 2010 and 2012 was conducted. Multivariate hierarchical analysis was used to examine the relationship between CPM likelihood and patient characteristics, with metropolitan statistical area (MSA) serving as a random effect. Patient characteristics included age group, BRCA1/2 carrier status, family history of breast cancer, breast surgery type, radiation therapy, drug therapy, and payer type. All MSAs in the United States were included, with areas outside MSAs within a given state aggregated into a single area for analytical purposes. RESULTS: Descriptive analysis demonstrated significant geographic variation in rates of CPM irrespective of risk inferred from primary malignancy treatment course (P<0.01 to <0.001). Odds of CPM were higher among BRCA1/2 carriers (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.52-2.06), followed by MSA (median OR among all MSAs was 1.61; 95% CI, 1.51-1.73) and family history of breast cancer (OR, 1.49; 95% CI, 1.28-1.53), respectively. Patients who were not tested for BRCA1/2 were less likely (OR, 0.66; 95% CI, 0.61-0.71) to undergo CPM than patients with a negative BRCA test. CONCLUSIONS: The large geographic variation we observed in CPM indicate a need to understand and optimize clinical decision-making.

17.
JAMA Netw Open ; 1(8): e185097, 2018 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-30646310

RESUMEN

Importance: Accurate prediction of outcomes among patients in intensive care units (ICUs) is important for clinical research and monitoring care quality. Most existing prediction models do not take full advantage of the electronic health record, using only the single worst value of laboratory tests and vital signs and largely ignoring information present in free-text notes. Whether capturing more of the available data and applying machine learning and natural language processing (NLP) can improve and automate the prediction of outcomes among patients in the ICU remains unknown. Objectives: To evaluate the change in power for a mortality prediction model among patients in the ICU achieved by incorporating measures of clinical trajectory together with NLP of clinical text and to assess the generalizability of this approach. Design, Setting, and Participants: This retrospective cohort study included 101 196 patients with a first-time admission to the ICU and a length of stay of at least 4 hours. Twenty ICUs at 2 academic medical centers (University of California, San Francisco [UCSF], and Beth Israel Deaconess Medical Center [BIDMC], Boston, Massachusetts) and 1 community hospital (Mills-Peninsula Medical Center [MPMC], Burlingame, California) contributed data from January 1, 2001, through June 1, 2017. Data were analyzed from July 1, 2017, through August 1, 2018. Main Outcomes and Measures: In-hospital mortality and model discrimination as assessed by the area under the receiver operating characteristic curve (AUC) and model calibration as assessed by the modified Hosmer-Lemeshow statistic. Results: Among 101 196 patients included in the analysis, 51.3% (n = 51 899) were male, with a mean (SD) age of 61.3 (17.1) years; their in-hospital mortality rate was 10.4% (n = 10 505). A baseline model using only the highest and lowest observed values for each laboratory test result or vital sign achieved a cross-validated AUC of 0.831 (95% CI, 0.830-0.832). In contrast, that model augmented with measures of clinical trajectory achieved an AUC of 0.899 (95% CI, 0.896-0.902; P < .001 for AUC difference). Further augmenting this model with NLP-derived terms associated with mortality further increased the AUC to 0.922 (95% CI, 0.916-0.924; P < .001). These NLP-derived terms were associated with improved model performance even when applied across sites (AUC difference for UCSF: 0.077 to 0.021; AUC difference for MPMC: 0.071 to 0.051; AUC difference for BIDMC: 0.035 to 0.043; P < .001) when augmenting with NLP at each site. Conclusions and Relevance: Intensive care unit mortality prediction models incorporating measures of clinical trajectory and NLP-derived terms yielded excellent predictive performance and generalized well in this sample of hospitals. The role of these automated algorithms, particularly those using unstructured data from notes and other sources, in clinical research and quality improvement seems to merit additional investigation.


Asunto(s)
Resultados de Cuidados Críticos , Enfermedad Crítica/mortalidad , Registros Electrónicos de Salud/clasificación , Procesamiento de Lenguaje Natural , Índice de Severidad de la Enfermedad , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Reproducibilidad de los Resultados , Estudios Retrospectivos
18.
IEEE Trans Med Imaging ; 36(12): 2578-2587, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29192887

RESUMEN

A single-scan dual-energy low-dose cone-beam CT (CBCT) imaging technique that exploits a multi-slit filter is proposed in this paper. The multi-slit filter installed between the x-ray source and the scanned object is reciprocated during a scan. The x-ray beams through the slits would generate relatively low-energy x-ray projection data, while the filtered beams would make high-energy projection data. An iterative image reconstruction algorithm that uses an adaptive-steepest-descent method to minimize image total-variation under the constraint of data fidelity was applied to reconstructing the image from the low-energy projection data. Since the high-energy projection data suffer from a substantially high noise level due to the beam filtration, we have developed a new algorithm that exploits the joint sparsity between the low- and high-energy CT images for image reconstruction of the high-energy CT image. The proposed image reconstruction algorithm uses a gradient magnitude image (GMI) of the low-energy CT image by regularizing the difference of GMIs of the low- and high-energy CT images to be minimized. The feasibility of the proposed technique has been demonstrated by the use of various phantoms in the experimental CBCT setup. Furthermore, based on the proposed dual-energy imaging, a material differentiation was performed and its potential utility has been shown. The proposed imaging technique produced promising results for its potential application to a low-dose single-scan dual-energy CBCT.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Estudios de Factibilidad , Cabeza/diagnóstico por imagen , Humanos , Fantasmas de Imagen
19.
Neurochem Res ; 42(5): 1533-1542, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28303501

RESUMEN

Tissue plasminogen activator (tPA) is the only recommended pharmacological treatment for acute ischemic stroke. However, tPA can induce intracerebral hemorrhage by blood-brain barrier breakdown through an increase in matrix metalloproteinases (MMPs). Previously, we showed that isoflurane postconditioning reduced intracranial hemorrhage following tPA treatment after cerebral ischemia. Here, we investigated the mechanism by which isoflurane postconditioning reduces tPA-induced MMP-2 and MMP-9 activation following hypoxia/reoxygenation (H/R) in brain endothelial cells. Mouse brain endothelial cells (bEnd.3) were exposed to 6 h of oxygen-glucose deprivation and 3 h of reoxygenation with tPA. Cells were treated with isoflurane for 1 h of the reoxygenation condition and the effect of isoflurane postconditioning on MMP-2 and MMP-9 activation was assessed. Involvement of low-density lipoprotein receptor-related protein (LRP), which is a receptor for tPA, and the extracellular signal-regulated kinase (ERK) and NF-κB pathway in isoflurane postconditioning was assessed using LRP inhibitor (receptor-associated protein, RAP) and ERK-1/2 inhibitor (PD98059). Isoflurane postconditioning decreased tPA-induced MMP-2 and MMP-9 activation under H/R. tPA treatment under H/R increased expression of LRP and the active form of NF-κB. Isoflurane postconditioning suppressed LRP expression, increased ERK-1/2 activation, and suppressed MMP-2 and MMP-9 activation, comparable to the effect of RAP. Activation of ERK-1/2, inhibition of NF-κB activation, and suppression of MMP-2 and MMP-9 activation by isoflurane postconditioning were abolished with PD98059 treatment. These finding indicate that isoflurane postconditioning inhibits tPA-induced MMP-2 and MMP-9 activation following H/R via the LRP/ERK/NF-κB pathway in bEnd.3.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Poscondicionamiento Isquémico/métodos , Isoflurano/farmacología , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Activador de Tejido Plasminógeno/farmacología , Anestésicos por Inhalación/farmacología , Animales , Hipoxia de la Célula/efectos de los fármacos , Hipoxia de la Célula/fisiología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Ratones , Activador de Tejido Plasminógeno/antagonistas & inhibidores
20.
Am J Chin Med ; 45(2): 319-335, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28231745

RESUMEN

Gastrodia elata Blume (GE) is a well-known kind of herb that has been used in traditional medicine for thousands of years. The extrusion of raw materials from it could improve flavor and enhance bioavailability in food and drug development. The purpose of this study is to investigate antitumor and immune boosting effects of extruded GE in human colon carcinoma cells, splenocytes, and mice-bearing CT26 colon carcinoma cell. Treatment with 100[Formula: see text][Formula: see text]g/mL of extruded GE decreased cell viability and induced the expression of Caspase-3 and Bax in HT29 cells ([Formula: see text]). When we performed DAPI staining, apoptotic bodies with condensed chromatin and fragmented nuclei, known as indicative of apoptotic morphology, increased 24[Formula: see text]h after treatment with 100[Formula: see text][Formula: see text]g/mL of extruded GE. Treatments with extruded GE significantly promoted splenocyte proliferation and IL-2 or IFN-[Formula: see text] secretion, compared with that of control cells ([Formula: see text]). The administration of extruded GE of 200 mg/kg/day decreased tumor growth and Ki-67 or [Formula: see text]-catenin expression in mice ([Formula: see text]). Additionally, we investigated the contents of compounds in extruded GE extracts using ultra performance liquid chromatography. The contents of p-hydroxylbenzyl alcohol and p-hydroxybenzaldehyde in extruded GE were 2.97[Formula: see text]mg/g and 0.04[Formula: see text]mg/g, respectively. It was supposed that antitumor and immunomodulatory effects of extruded GE might exert by the p-hydroxylbenzyl alcohol and p-hydroxybenzaldehyde of many compositions analyzed from extruded GE. These results suggest that extruded GE have the potential to be developed into a natural pharmaceutical and functional food as a cancer chemopreventive agent.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Gastrodia , Factores Inmunológicos , Extractos Vegetales/farmacología , Bazo/inmunología , Animales , Antineoplásicos Fitogénicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/genética , Expresión Génica/efectos de los fármacos , Células HT29 , Humanos , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/uso terapéutico , Bazo/citología , beta Catenina/genética , beta Catenina/metabolismo
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