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1.
Sci Data ; 10(1): 240, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37100784

RESUMEN

Computer-aided diagnosis systems in adult chest radiography (CXR) have recently achieved great success thanks to the availability of large-scale, annotated datasets and the advent of high-performance supervised learning algorithms. However, the development of diagnostic models for detecting and diagnosing pediatric diseases in CXR scans is undertaken due to the lack of high-quality physician-annotated datasets. To overcome this challenge, we introduce and release PediCXR, a new pediatric CXR dataset of 9,125 studies retrospectively collected from a major pediatric hospital in Vietnam between 2020 and 2021. Each scan was manually annotated by a pediatric radiologist with more than ten years of experience. The dataset was labeled for the presence of 36 critical findings and 15 diseases. In particular, each abnormal finding was identified via a rectangle bounding box on the image. To the best of our knowledge, this is the first and largest pediatric CXR dataset containing lesion-level annotations and image-level labels for the detection of multiple findings and diseases. For algorithm development, the dataset was divided into a training set of 7,728 and a test set of 1,397. To encourage new advances in pediatric CXR interpretation using data-driven approaches, we provide a detailed description of the PediCXR data sample and make the dataset publicly available on https://physionet.org/content/vindr-pcxr/1.0.0/ .


Asunto(s)
Radiografía Torácica , Enfermedades Torácicas , Niño , Humanos , Algoritmos , Diagnóstico por Computador/métodos , Radiografía Torácica/métodos , Estudios Retrospectivos , Enfermedades Torácicas/diagnóstico por imagen
2.
Eval Rev ; 46(2): 103-137, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34983196

RESUMEN

BACKGROUND: Corruption affects businesses in various ways. Anti-corruption, on the other hand, can improve the institutions of the country as well as business operations. Vietnam, as a socialist-oriented country with an ongoing high-profile anti-corruption campaign, provides us a unique setting to evaluate the impacts of anti-corruption on corporate performance. OBJECTIVES: We address two questions: (1) what is the effect of anti-corruption on the performance of private-owned firms in Vietnam? and (2) how does anti-corruption influence the performance of firms with state ownership (FSOs) in Vietnam? RESEARCH DESIGN: To investigate the impact of anti-corruption on performance of firms with different ownership settings, we use the establishment of the Central Anti-Corruption Steering Committee of Vietnam as a quasi-natural experiment for difference-in-differences analysis. We generate treatment effects of private holding and the state block ownership. To validate the findings, we construct a novel news-based anti-corruption index from Vietnamese online newspapers and use it in a robustness test to evaluate anti-corruption's impacts on firm performance. RESULTS AND CONCLUSIONS: We find a positive impact of the anti-corruption campaign on private firms' performance, supporting the social norm perspective of how corruption affects businesses. The empirical results indicate a negative impact of the campaign on FSOs' performance. The findings suggest that anti-corruption benefits private firms via improving the institutional quality of the country while improving the financial transparency of FSOs. Our study provides a method for measuring anti-corruption which is virtually unobservable and absent in the literature. The findings have implications for policymaking in contemporary Vietnam.


Asunto(s)
Comercio , Propiedad , Vietnam
3.
Res Vet Sci ; 134: 64-68, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33310555

RESUMEN

The ability of infectious laryngotracheitis virus (ILTV) to replicate in organs outside of the upper respiratory tract and conjunctiva associated-lymphoid tissues is still not well understood. This study investigated the tissue distribution of an Australian field strain of ILTV (class 9) on birds experimentally inoculated via eye-drop at 7 days of age by using quantitative PCR (qPCR) and immunohistochemistry. Tissues including conjunctiva, caecal tonsil, kidney, liver, lung, spleen, thymus, trachea and blood were collected from sham-inoculated (control group; n = 2) and ILTV-inoculated (n = 8) birds at 7 days post-inoculation (dpi). Blood was collected from 13 infected birds at 14 dpi and fractionated using ficoll-paque. At 7 dpi, the highest detection rate and genomic copies (GC) were in conjunctiva (8/8; 8.08 ± 0.48 log10 GC/mg) followed by trachea (8/8; 4.64 ± 0.48) and thymus (8/8; 4.52 ± 0.48), kidney (8/8; 3.97 ± 0.48), lung (8/8; 3.65 ± 0.48), spleen (8/8; 3.55 ± 0.48), liver (8/8; 3.51 ± 0.48), caecal tonsil (7/8; 3.76 ± 0.48) and plasma (4/8; 2.40 ± 0.48 log10 GC/ml). ILTV antigen was only detected in conjunctiva (7/8), trachea (6/8) and lung (4/8) samples. At 14 dpi, ILTV detection rate and genomic copies in buffy coat cells were 12/13 and 2.86 ± 0.39 log10 GC/mg, respectively while those of plasma were 11/13 and 4.29 ± 0.39 log10 GC/ml and red blood cell were 3/13 and 0.36 ± 0.39 log10 GC/mg. In conclusion, ILTV DNA was detected in a wide range of tissues and blood fractions but ILTV antigen was only detected in respiratory organs and conjunctiva.


Asunto(s)
Pollos , Infecciones por Herpesviridae/veterinaria , Herpesvirus Gallináceo 1/aislamiento & purificación , Enfermedades de las Aves de Corral/virología , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Animales , Australia , Pollos/genética , Pollos/virología , Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/virología , Herpesvirus Gallináceo 1/genética , Herpesvirus Gallináceo 1/inmunología , Inmunohistoquímica/veterinaria , Tejido Linfoide/virología , Enfermedades de las Aves de Corral/sangre
4.
Sensors (Basel) ; 20(17)2020 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-32842695

RESUMEN

This paper pursues a simultaneous modal parameter anomaly detection paradigm to structural damage identification inferred from vibration-based structural health monitoring (SHM) sensors, e.g., accelerometers. System Realization Using Information Matrix (SRIM) method is performed in short duration sweeping time windows for identification of state matrices, and then, modal parameters with enhanced automation. Stable modal poles collected from stability diagrams are clustered and fed into the Gaussian distribution-based anomaly detection platform. Different anomaly thresholds are examined both on frequency and damping ratio terms taking two testbed bridge structures as application means, and simplistic Boolean Operators are performed to merge univariate anomalies. The first bridge is a reinforced concrete bridge subjected to incremental damage through a series of seismic shake table experiments conducted at the University of Nevada, Reno. The second bridge is a steel arch structure at Columbia University Morningside Campus, which reflects no damage throughout the measurements, unlike the first one. Two large-scale implementations indicate the realistic performance of automated modal analysis and anomaly recognition with minimal human intervention in terms of parameter extraction and learning supervision. Anomaly detection performance, presented in this paper, shows variation according to the designated thresholds, and hence, the information retrieval metrics being considered. The methodology is well-fitted to SHM problems which require sole data-driven, scalable, and fully autonomous perspectives.

5.
Avian Dis ; 64(4): 565-570, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33647150

RESUMEN

Dust collected from the poultry house has been increasingly used as a population-level sample to monitor the presence of pathogens or to evaluate the administration of live vaccines. However, there are no guidelines for the storage of this sample type. This study investigated the stability of infectious laryngotracheitis virus (ILTV), a DNA virus, and infectious bronchitis virus (IBV), an RNA virus, in poultry dust kept under temperature and moisture conditions that mimic on-farm and laboratory storage. Dust samples were collected from chicks spray vaccinated with a live IBV vaccine and inoculated with a field ILTV strain via eye drop. Samples were stored under different moisture conditions (dry = 2% moisture, moist = 22%-71% moisture) and temperatures (-20, 4, 25, and 37 C) for different durations (0, 7, and 14 days, and 1, 2, 3, and 4 mo) in a factorial arrangement, followed by quantitative PCR for detection of virus genome copies (GC). The length of storage, moisture level, and storage temperature affected the viral genome load for ILTV and IBV but did not affect the number of positive samples for each virus. All treatment combinations were ILTV positive for at least 4 mo. In dry dust samples, all storage temperatures or durations had quantifiable ILTV or IBV GC. Moisture addition had a detrimental effect on viral genome load, causing an overall reduction of 0.3 log 10 for ILTV GC (7.29 and 6.97 log 10, P = 0.0001), and 1.3 log 10 for IBV GC (5.95 and 4.66 log 10, P = 0.0001), which are unlikely to have biologic significance. In conclusion, dry dust can be stored at any temperature up to 37 C for at least 4 mo without loss in qPCR detection of ILTV or IBV GC. Collection or storage of moist dust should be avoided, or air drying prior to storage is recommended if only moist dust is available.


Asunto(s)
Enfermedades de las Aves/diagnóstico , Infecciones por Coronavirus/veterinaria , Genoma Viral , Inestabilidad Genómica , Infecciones por Herpesviridae/veterinaria , Herpesvirus Gallináceo 1/aislamiento & purificación , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Reacción en Cadena de la Polimerasa/veterinaria , Animales , Enfermedades de las Aves/virología , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Polvo/análisis , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/virología , Herpesvirus Gallináceo 1/genética , Virus de la Bronquitis Infecciosa/genética , Manejo de Especímenes/veterinaria
6.
J Phys Chem B ; 119(33): 10478-87, 2015 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-26228450

RESUMEN

We have studied the dimer of amyloid beta peptide Aß of 40 residues by means of all-atom replica exchange molecular dynamics. The Aß-dimers have been found to be the smallest toxic species in Alzheimer's disease, but their inherent flexibilities have precluded structural characterization by experimental methods. Though the 24-µs-scale simulation reveals a mean secondary structure of 18% ß-strand and 10% α helix, we find transient configurations with an unstructured N-terminus and multiple ß-hairpins spanning residues 17-21 and 30-36, but the antiparallel and perpendicular peptide orientations are preferred over the parallel organization. Short-lived conformational states also consist of all α topologies, and one compact peptide with ß-sheet structure stabilized by a rather extended peptide with α-helical content. Overall, this first all-atom study provides insights into the equilibrium structure of the Aß1-40 dimer in aqueous solution, opening a new avenue for a comprehensive understanding of the impact of pathogenic and protective mutations in early-stage Alzheimer's disease on a molecular level.


Asunto(s)
Péptidos beta-Amiloides/química , Simulación de Dinámica Molecular , Fragmentos de Péptidos/química , Multimerización de Proteína , Estructura Secundaria de Proteína , Termodinámica , Agua/química
7.
Poult Sci ; 92(5): 1322-30, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23571342

RESUMEN

Many different components of the retina can be affected by inherited degenerative diseases causing blindness. Currently, 5 different mutant strains of chicken have already been studied as potential models for inherited retinal degeneration; however, the potential for the blind strain of White Leghorns, called Smoky Joe (SJ), as a model remains unknown. Ocular symptoms observed within homozygous SJ birds show the birds have varying levels of blindness at hatch and by 8 wk posthatch are completely blind, but details about the development of the blindness are unclear (Salter et al., 1997). The objective of this study was to characterize the retinal development of blind and sighted SJ chicks during embryogenesis, and to monitor the numbers of the retinal cells with cell-type-specific markers. Blind SJ chicks showed less retinal cells throughout embryogenesis compared with sighted SJ chicks (P < 0.0001). Based on the histological analysis, it was determined that amacrine cells within the inner nuclear layer were the most affected cell type, showing lower numbers in the blind SJ compared with the sighted; amacrine cell development was also delayed in the blind birds, beginning 2 d later than in sighted SJ birds. Photoreceptors were also scarcely detected within the blind SJ and potentially may be an additional target of developmental impairment. Further analysis on posthatch SJ will aid in determining degenerative characteristics of a fully developed retina and its cells.


Asunto(s)
Ceguera/embriología , Células Fotorreceptoras/patología , Retina/embriología , Retina/patología , Degeneración Retiniana/embriología , Animales , Ceguera/metabolismo , Ceguera/patología , Embrión de Pollo , Pollos , Femenino , Masculino , Microscopía Fluorescente , Modelos Animales , Células Fotorreceptoras/citología , Células Fotorreceptoras/metabolismo , Retina/citología , Retina/metabolismo , Degeneración Retiniana/metabolismo , Degeneración Retiniana/patología
8.
Adv Exp Med Biol ; 643: 181-90, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19239148

RESUMEN

Effects of taurine and guanidinoethanesulfonic acid (GES), a taurine transport inhibitor, on the expression and phosphorylation of cellular proteins in C6 glial cells were examined using two-dimensional (2-D) gel electrophoresis and 2-D immunoblots. 2-D gels stained with Coomassie Blue or SYPRO Ruby showed differential distribution patterns of cellular proteins in the control, taurine-supplemented and GES-supplemented cells. 2-D immunoblot analysis using the anti-phosphotyrosine antibody recognized only few immuno-reactive proteins in all three samples, and their distribution patterns were different. On the other hand, 2-D immunoblot analysis using the anti-phosphothreonine antibody recognized many immuno-reactive proteins with distinctly different distribution patterns in the control, taurine-supplemented and GES-supplemented cells. In GES-supplemented cells, the relative number of the anti-phosphotyrosine immuno-reactive protein spots increased modestly, whereas the relative number of the anti-phosphothreonine immuno-reactive protein spots decreased markedly than those in the control and taurine-supplemented cells.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Proteínas/metabolismo , Taurina/análogos & derivados , Taurina/farmacología , Línea Celular , Electroforesis en Gel Bidimensional , Fosforilación
9.
Adv Exp Med Biol ; 643: 503-11, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19239182

RESUMEN

We have investigated the underlying mechanism of the CsA-induced inhibition of taurine transport using a cell line permanently expressing the mouse taurine transporter (mTauT) tagged with the green-fluorescence protein (GFP). CsA inhibited the uptake activity of the expressed mTauT.GFP fusion protein in both dose and time dependent manner. Surface biotinylation assay revealed that the CsA-treatment reduced the relative surface abundance of the taurine transporter without affecting its total expression level. CsA treatment reduced both the taurine uptake and the relative surface abundance of the transporter by similar magnitudes. Conversely, when the CsA was washed off, both the uptake and the relative surface abundance of the transporter recovered fully to the control level. Remarkably, the recovery process was insensitive to the protein synthesis inhibitor cycloheximide. These results suggested that the CsA inhibited taurine transport by altering the surface abundance, possibly by internalization of the expressed taurine transporters.


Asunto(s)
Ciclosporina/farmacología , Glicoproteínas de Membrana/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Taurina/metabolismo , Animales , Transporte Biológico , Western Blotting , Línea Celular , Proteínas Fluorescentes Verdes/genética , Humanos , Glicoproteínas de Membrana/genética , Proteínas de Transporte de Membrana/genética , Ratones
10.
J Biol Chem ; 279(3): 1838-44, 2004 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-14597622

RESUMEN

The promyelocytic leukemia protein (PML) plays an essential role in multiple pathways of apoptosis. Our previous study showed that PML enhances tumor necrosis factor-induced apoptosis by inhibiting the NFkappaB survival pathway. To continue exploring the mechanism of PML-induced apoptosis, we performed a DNA microarray screening of PML target genes using a PML-inducible stable cell line. We found that Survivin was one of the downstream target genes of PML. Cotransfection experiments demonstrated that PML4 repressed transactivation of the Survivin promoter in an isoform-specific manner. Western blot analysis demonstrated that induced PML expression down-regulated Survivin. Inversely, PML knockdown by siRNA up-regulated Survivin expression. A substantial increase in Survivin expression was found in PML-deficient cells. Re-expression of PML in PML-/- mouse embryo fibroblasts down-regulated the expression of Survivin. Furthermore, cells arrested at the G2/M cell cycle phase expressed a high level of Survivin and a significantly lower level of PML. Overexpression of PML in A549 cells reduced Survivin expression leading to massive apoptotic cell death associated with activation of procaspase 9, caspase 3, and caspase 7. Together, our results demonstrate a novel mechanism of PML-induced apoptosis by down-regulation of Survivin.


Asunto(s)
Apoptosis , Proteínas Asociadas a Microtúbulos/genética , Proteínas de Neoplasias/fisiología , Proteínas Nucleares , Proteínas Represoras/fisiología , Factores de Transcripción/fisiología , Ciclo Celular , Línea Celular , Regulación hacia Abajo , Regulación de la Expresión Génica , Humanos , Proteínas Inhibidoras de la Apoptosis , Proteínas Asociadas a Microtúbulos/fisiología , Regiones Promotoras Genéticas , Proteína de la Leucemia Promielocítica , Receptores de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Survivin , Activación Transcripcional , Proteínas Supresoras de Tumor
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