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1.
Sci Rep ; 13(1): 19732, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37957283

RESUMEN

This study evaluated how often clinically significant lung nodules were detected unexpectedly on chest radiographs (CXR) by artificial intelligence (AI)-based detection software, and whether co-existing findings can aid in differential diagnosis of lung nodules. Patients (> 18 years old) with AI-detected lung nodules at their first visit from March 2021 to February 2022, except for those in the pulmonology or thoracic surgery departments, were retrospectively included. Three radiologists categorized nodules into malignancy, active inflammation, post-inflammatory sequelae, or "other" groups. Characteristics of the nodule and abnormality scores of co-existing lung lesions were compared. Approximately 1% of patients (152/14,563) had unexpected lung nodules. Among 73 patients with follow-up exams, 69.9% had true positive nodules. Increased abnormality scores for nodules were significantly associated with malignancy (odds ratio [OR] 1.076, P = 0.001). Increased abnormality scores for consolidation (OR 1.033, P = 0.040) and pleural effusion (OR 1.025, P = 0.041) were significantly correlated with active inflammation-type nodules. Abnormality scores for fibrosis (OR 1.036, P = 0.013) and nodules (OR 0.940, P = 0.001) were significantly associated with post-inflammatory sequelae categorization. AI-based lesion-detection software of CXRs in daily practice can help identify clinically significant incidental lung nodules, and referring accompanying lung lesions may help classify the nodule.


Asunto(s)
Neoplasias Pulmonares , Neoplasias , Humanos , Adolescente , Inteligencia Artificial , Pulmón , Estudios Retrospectivos , Inflamación , Neoplasias Pulmonares/diagnóstico por imagen , Radiografía Torácica
2.
Environ Monit Assess ; 195(11): 1289, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37821640

RESUMEN

Land subsidence is the gradual or sudden dropping of the ground surface developed by increasing the total stress. Most studies have discussed the relationship between land subsidence with groundwater level. However, there is a lack of discussion on groundwater environmental changes after occurring land subsidence. This study aimed to evaluate the hydrogeological and water chemistry characteristics of construction sites with land subsidence. Land subsidence in the Yangyang coastal area occurred suddenly on August 3, 2022, when the retaining wall of the construction collapsed. The groundwater level was measured three times, and water samples were collected twice between August 5, 2022, and September 5, 2022, for laboratory analysis. After land subsidence occurred, the average groundwater level was - 19.91 m ground level (GL) on August 9, 2022, and finally decreased to - 19.21 m GL on September 05, 2022. The groundwater levels surrounding the construction site gradually increased for a month. The electrical conductivity value measured at the monitoring wells ranged from 89 to 7800 µS/cm, and four wells exceeded the measurement limit near the groundwater leaked points. The highest mixing ratio of leaked water samples, collected on August 9, 2022, was 27.6%. Furthermore, the fresh groundwater-saltwater interface depth was estimated to be above the construction bottom. Although groundwater levels recovered, the groundwater quality continuously is affected by saltwater. This finding could contribute to understanding the hydrogeological characteristics surrounding construction sites with land subsidence and provide insight into the hydrochemical evolution process during declined groundwater levels in coastal aquifers.


Asunto(s)
Agua Subterránea , Agua , Agua/análisis , Monitoreo del Ambiente , Agua Subterránea/análisis , Agua Dulce , República de Corea
3.
Polymers (Basel) ; 15(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37447561

RESUMEN

The wastewater generated from the semiconductor production process contains a wide range and a large number of harmful substances at high concentrations. Excessive exposure to fluoride can lead to life-threatening effects such as skin necrosis and respiratory damage. Accordingly, a guideline value of fluoride ions in drinking water was 1.5 mg L-1 recommended by the World Health Organization (WHO). Polyvinylidene fluoride (PVDF) has the characteristics of excellent chemical and thermal stability. Boehmite (AlOOH) is a mineral and has been widely used as an adsorbent due to its high surface area and strong adsorption capacity for fluoride ions. It can be densely coated on negatively charged surfaces through electrostatic interaction due to its positively charged surface. In this study, a composite membrane was fabricated by a simple and economical dip coating of a commercial melamine sponge (MS) with PVDF and boehmite to remove fluoride ions from semiconductor wastewater. The prepared MS-PVDF-Boehmite composite membrane showed a high removal efficiency for fluoride ions in both incubation and filtration. By the incubation process, the removal efficiency of fluoride ions was 55% within 10 min and reached 80% after 24 h. In the case of filtration, the removal efficiency was 95.5% by 4 cycles of filtering with a flow rate of 70 mL h-1. In addition, the removal mechanism of fluoride ions on MS-PVDF-Boehmite was also explored by using Langmuir and Freundlich isotherms and kinetic analysis. (R2-1) From the physical, chemical, thermal, morphological, and mechanical analyses of present materials, this study provides an MS-PVDF-Boehmite composite filter material that is suitable for fluoride removal applications due to its simple fabrication process, cost-effectiveness, and high performance.

4.
Cell Commun Signal ; 21(1): 107, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37161542

RESUMEN

BACKGROUND: Ex vivo cultivation is a promising strategy for increasing the number of NK cells and enhancing their antitumor activity prior to clinical application. Recent studies show that stimulation with 25KDa branched polyethylenimine (25KbPEI) generates NK cells with enhanced antitumor activity. To better understand how 25KbPEI primes NK cells, we explored the mechanism underlying increase in production of IFN-γ. METHODS: Chemical priming was performed on NK-92MI cells by incubating them with 5 µg/ml of 25KbPEI. The production of IFN-γ was evaluated by RT-qPCR, ELISA, and Flow cytometry. By evaluating the effect of pharmacological inhibition of ERK/mTOR-eIF4E signaling pathways on IFN-γ translation, the function of these signaling pathways in IFN-γ translation was examined. To comprehend the level of 25KbPEI activity on immune-related components in NK cells, RNA sequencing and proteomics analyses were conducted. RESULTS: 25KbPEI enhances the production of IFN-γ by NK cells without transcriptional activation. Activation of ERK and mTOR signaling pathways was found to be associated with 25KbPEI-mediated calcium influx in NK cells. The activation of ERK/mTOR signaling was linked to the phosphorylation of 4E-BP1, which resulted in the activation of translation initiation complex and subsequent IFN-γ translation. Analysis of RNA sequencing and proteomics data revealed that the activity of 25KbPEI to improve translation efficiency in NK cells could be extended to additional immune-related molecules. CONCLUSIONS: This study provides substantial insight into the process by which 25KbPEI primes NK cells. Our data demonstrated that the 25KbPEI mediated activation of ERK/mTOR signaling and subsequent stimulation of eIF4E is the primary mechanism by which the chemical stimulates translation of IFN-γ in NK cells. Video abstract.


Asunto(s)
Interferón gamma , Polietileneimina , Factor 4E Eucariótico de Iniciación , Células Asesinas Naturales , Calcio
5.
Sci Total Environ ; 887: 164112, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37172846

RESUMEN

In recent decades, environmental pollution from microplastic (MPs: <5 mm) and climate change have received international attention. However, these two issues have been primarily investigated separately hitherto, although they exhibit a cause-and-effect relationship. Studies considering MPs and climate change as causal entities have focused only on MP pollution in marine environments as a contributor to climate change. Meanwhile, systematic causal studies have not been performed inadequately to understand the role of soil, which is a primary terrestrial sink of greenhouse gases (GHGs) in the context of MP pollution, in climate change. In this study, the causal effect of soil MP pollution on GHG emissions as direct and indirect contributors to climate change is systematically analyzed. The mechanisms underlying the contribution of soil MPs to climate change are discussed, and future research perspectives are suggested. Approximately 121 research manuscripts pertaining to MP pollution and its associated effects on GHGs, carbon sinks, and soil respiration, recorded between 2018 and 2023, are selected and cataloged from seven database categories in PubMed, Google Scholar, Nature's database, and Web of Science. Several studies demonstrated that soil MP pollution directly contributes to climate change by accelerating the emission of GHGs from the soil to the atmosphere and indirectly by promoting soil respiration and adversely affecting natural carbon sinks, such as trees. Other studies correlated the release of GHGs from the soil to mechanisms such as the alteration of soil aeration, methanogen activity, and carbon and nitrogen cycles, and improved the abundance of carbon and nitrogen soil microbial functional genes adhering to plant roots to create anoxic conditions for plant growth. In general, soil MP pollution increases the release of GHGs into the atmosphere, thereby contributing to climate change. However, further research is to be conducted by investigating the underlying mechanisms using more practical field-scale data.


Asunto(s)
Cambio Climático , Gases de Efecto Invernadero , Microplásticos , Plásticos , Dióxido de Carbono/análisis , Metano/análisis , Óxido Nitroso/análisis , Gases de Efecto Invernadero/análisis , Contaminación Ambiental , Carbono , Suelo
6.
Oncoimmunology ; 12(1): 2190671, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36950218

RESUMEN

Triple-negative breast cancer (TNBC) is the most challenging subtype of breast cancer because of its aggressive behavior and the limited therapeutic strategies available. In the last decade, immunotherapy has become a promising treatment to prolong survival in advanced solid cancers including TNBC. However, the efficacy of immunotherapy in solid cancers remains limited because solid tumors contain few tumor-infiltrating lymphocytes. Here, we show that targeting an ETS transcription factor ELK3 (ELK3) recruits immune cells including natural killer (NK) cells into tumors via the chemotactic activity of chemokine. ELK3 depletion increases CXCL16 expression level and promotes NK cell cytotoxicity through CXCL16-mediated NK cell recruitment in TNBC. In silico analysis showed that ELK3 is negatively correlated with CXCL16 expression in breast cancer patient samples. Low expression of ELK3 and high expression of CXCL16 were associated with a better prognosis. Low expression of ELK3 and high expression of CXCL16 were associated with increased expression of NK cell-related genes. Our findings demonstrate that the ELK3-CXCL16 axis modulates NK cell recruitment to increase NK cell cytotoxicity, suggesting that targeting the ELK3 gene could be an adjuvant strategy for increasing the efficacy of immunotherapy in TNBC.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Línea Celular Tumoral , Células Asesinas Naturales/metabolismo , Inmunoterapia , Proteínas Proto-Oncogénicas c-ets/genética , Proteínas Proto-Oncogénicas c-ets/metabolismo , Quimiocina CXCL16/genética , Quimiocina CXCL16/metabolismo
7.
J Immunother Cancer ; 10(8)2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-36028281

RESUMEN

BACKGROUND: Due to their powerful immune surveillance activity and ability to kill and clear cancer cells, natural killer (NK) cells are an emerging anticancer immunotherapeutic agent. Therefore, there is much interest in developing efficient technologies that further enhance the therapeutic antitumor efficacy of NK cells. METHODS: To produce chemically primed NK cells, we screened polymers with various electric charges and examined their ability to enhance the cytotoxicity of NK cells. The effect of primary amine and electric charges of 25 kDa branched polyethylenimine (25KbPEI) was investigated by fluorination of the chemical. The role of 25KbPEI in determining the major priming mechanism was investigated in terms of calcium influx into NK cells. In vivo therapeutic efficacy of chemically primed NK cells was evaluated against solid tumor mouse model of triple negative breast and ovarian cancers. RESULTS: Chem_NK that was produced by the priming activity of 25KbPEI showed potent antitumor activity to various cancer cells. Chem_NK showed an activated phenotype, which manifests as increased expression of activating/adhesion/chemokine receptors and perforin accumulation, leading to enhanced migration ability and antitumor activity. Chem_NK display potent therapeutic efficacy against in vivo mouse model of triple negative breast and ovarian cancers. Fluorination of the primary amine group reduces the activity of 25KbPEI to prime NK cells, indicating that the cationic charge on the chemical plays a critical role in NK cell activation. A major priming mechanism was 25KbPEI-mediated calcium influx into NK cells, which occurred mainly via the Ca2+-permeable non-selective cation channel transient receptor potential melastatin 2. CONCLUSIONS: NK cells can be chemically primed with 25KbPEI to express potent antitumor activity as well as enhanced migration ability. Because PEI is a biocompatible and Food and Drug Administration-approved chemical for biomedical use, these results suggest a cost-effective and simple method of producing therapeutic NK cells.


Asunto(s)
Antineoplásicos , Neoplasias Ováricas , Neoplasias de la Mama Triple Negativas , Aminas , Animales , Calcio , Línea Celular Tumoral , Femenino , Humanos , Inmunoterapia , Células Asesinas Naturales , Ratones , Polietileneimina , Estados Unidos
8.
J Immunother Cancer ; 10(7)2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35858708

RESUMEN

BACKGROUND: Triple negative breast cancer (TNBC) is the most lethal subtype of breast cancer due to its aggressive behavior and frequent development of resistance to chemotherapy. Although natural killer (NK) cell-based immunotherapy is a promising strategy for overcoming barriers to cancer treatment, the therapeutic efficacy of NK cells against TNBC is below expectations. E26 transformation-specific transcription factor ELK3 (ELK3) is highly expressed in TNBCs and functions as a master regulator of the epithelial-mesenchymal transition. METHODS: Two representative human TNBC cell lines, MDA-MB231 and Hs578T, were exposed to ELK3-targeting shRNA or an ELK3-expressing plasmid to modulate ELK3 expression. The downstream target genes of ELK3 were identified using a combined approach comprising gene expression profiling and molecular analysis. The role of ELK3 in determining the immunosensitivity of TNBC to NK cells was investigated in terms of mitochondrial fission-fusion transition and reactive oxygen species concentration both in vitro and in vivo. RESULTS: ELK3-dependent mitochondrial fission-fusion status was linked to the mitochondrial superoxide concentration in TNBCs and was a main determinant of NK cell-mediated immune responses. We identified mitochondrial dynamics proteins of 51 (Mid51), a major mediator of mitochondrial fission, as a direct downstream target of ELK3 in TNBCs. Also, we demonstrated that expression of ELK3 correlated inversely with that of Mid51, and that the ELK3-Mid51 axis is associated directly with the status of mitochondrial dynamics. METABRIC analysis revealed that the ELK3-Mid51 axis has a direct effect on the immune score and survival of patients with TNBC. CONCLUSIONS: Taken together, the data suggest that NK cell responses to TNBC are linked directly to ELK3 expression levels, shedding new light on strategies to improve the efficacy of NK cell-based immunotherapy of TNBC.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Línea Celular Tumoral , Transición Epitelial-Mesenquimal , Humanos , Células Asesinas Naturales , Dinámicas Mitocondriales , Proteínas Proto-Oncogénicas c-ets , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/terapia
9.
Int J Mol Sci ; 23(7)2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35409069

RESUMEN

Current therapeutic strategies for gastric cancer, including surgery and chemotherapy improve patient survival; however, the survival rate of patients with metastatic gastric cancer is very low. The molecular mechanisms underlying the dissemination of gastric cancer cells to distant organs are currently unknown. Here, we demonstrate that the E26 transformation-specific (ETS) transcription factor ELK3 (ELK3) gene is required for the migration and invasion of gastric cancer cells. The ELK3 gene modulates the expression of extracellular matrix (ECM) remodeling-related genes, such as bone morphogenetic protein (BMP1), lysyl oxidase like 2 (LOXL2), Snail family transcriptional repressor 1 (SNAI1), serpin family F member 1 (SERPINF1), decorin (DCN), and nidogen 1 (NID1) to facilitate cancer cell dissemination. Our in silico analyses indicated that ELK3 expression was positively associated with these ECM remodeling-related genes in gastric cancer cells and patient samples. The high expressions of ELK3 and other ECM remodeling-related genes were also closely associated with a worse prognosis of patients with gastric cancer. Collectively, these findings suggest that ELK3 acts as an important regulator of gastric cancer cell dissemination by regulating ECM remodeling.


Asunto(s)
Neoplasias Gástricas , Línea Celular Tumoral , Movimiento Celular/genética , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Humanos , Proteínas Proto-Oncogénicas c-ets/genética , Proteínas Proto-Oncogénicas c-ets/metabolismo , Neoplasias Gástricas/genética
10.
J Clin Med ; 11(7)2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35407380

RESUMEN

(1) Background: Prolonged neck flexion is thought to cause harmful loading on the cervical spine. Along with the degenerative process, cervical alignment tends to change toward lordotic curvature. The association between cervical alignment and cervical spondylosis remains unclear. (2) Methods: Three raters retrospectively assessed cervical radiographies of outpatients at a tertiary center in 2019 using degenerative cervical spondylosis score (DCS score; a newly developed scoring system), C2-7 absolute rotational angle (ARA), and C2-7 sagittal vertical axis (SVA). (3) Results: A total of 561 patients were included in the analysis. Multiple regression analysis with adjustments for age and sex revealed that C2-7 ARA, rather than SVA, was a significant parameter for degenerative spondylosis. The interaction between age and C2-7 ARA was significant, indicating that the increase in DCS score with increasing age was more pronounced in patients with kyphotic cervical alignment. The direct effect of age on DCS score was 0.349 (95% CI 0.319 to 0.380, p < 0.001) and the proportion of the mediation effect of C2-7 ARA was −0.125 (p < 0.001). (4) Conclusions: C2-7 ARA was significantly associated with DCS after adjustment for both age and sex. Subjects with more kyphotic cervical alignment showed a greater correlation between increased DCS score and older age.

11.
RSC Adv ; 8(31): 17417-17420, 2018 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35539227

RESUMEN

In this paper, we demonstrate high-performance organic logic circuits based on precisely controlled organic single-crystal arrays. Well-aligned microrod shaped 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) single-crystal organic thin-film-transistors (OTFTs) were fabricated via solvent mediated molecular tailoring with a polymeric sacrificial layer, exhibiting saturation mobility of >2 cm2 V-1 s-1. Using this approach, precise placement of organic crystal arrays in a controlled orientation was successfully achieved, enabling the fabrication of OTFT-based inverter circuits with a gain of 1.37 (V V-1). Furthermore, it was demonstrated that, by varying the number of single-crystal microrods, the device dimension and corresponding circuit performance can be modulated. A high-performance inverter operation with various interdigitating single-crystal microrod arrays can thus be achieved.

12.
Nanoscale ; 9(43): 16711-16721, 2017 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-29067384

RESUMEN

Purified semiconducting single-walled carbon nanotubes (sc-SWCNTs) have been researched for optoelectronic applications due to their high absorption coefficient from the visible to even the near-infrared (NIR) region. Nevertheless, the insufficient electrical characteristics and incompatibility with conventional CMOS processing have limited their wide utilization in this emerging field. Here, we demonstrate highly detective and wide spectral/dynamic range phototransistors incorporating floated heterojunction active layers which are composed of low-temperature sol-gel processed n-type amorphous indium gallium zinc oxide (a-IGZO) stacked with a purified p-type sc-SWCNT layer. To achieve a high and broad spectral/dynamic range photo-response of the heterogeneous transistors, photochemically functionalized sc-SWCNT layers were carefully implemented onto the a-IGZO channel area with a floating p-n heterojunction active layer, resulting in the suppression of parasitic charge leakage and good bias driven opto-electrical properties. The highest photosensitivity (R) of 9.6 × 102 A W-1 and a photodetectivity (D*) of 4 × 1014 Jones along with a dynamic range of 100-180 dB were achieved for our phototransistor in the spectral range of 400-780 nm including continuous and minimal frequency independent behaviors. More importantly, to demonstrate the diverse application of the ultra-flexible hybrid photosensor platform as skin compatible electronics, the sc-SWCNT/a-IGZO phototransistors were fabricated on an ultra-thin (∼1 µm) polyimide film along with a severe static and dynamic electro-mechanical test. The skin-like phototransistors showed excellent mechanical stability such as sustainable good electrical performance and high photosensitivity in a wide dynamic range without any visible cracks or damage and little noise interference after being rolled-up on the 150 µm-thick optical fiber as well as more than 1000 times cycling.

13.
Korean J Radiol ; 18(2): 299-308, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28246510

RESUMEN

Pancreatic surgery remains the only curative treatment for pancreatic neoplasms, and plays an important role in the management of medically intractable diseases. Since the original Whipple operation in the 20th century, surgical techniques have advanced, resulting in decreased postoperative complications and better clinical outcomes. Normal postoperative imaging findings vary greatly depending on the surgical technique used. Radiologists are required to be familiar with the normal postoperative imaging findings, in order to distinguish from postoperative complications or tumor recurrence. In this study, we briefly review a variety of surgical techniques for the pancreas, and present the normal postoperative computed tomography findings.


Asunto(s)
Páncreas/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Humanos , Recurrencia Local de Neoplasia , Pancreatectomía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pancreatoyeyunostomía , Complicaciones Posoperatorias/prevención & control , Tomografía Computarizada por Rayos X
14.
Clin Nucl Med ; 41(4): 296-301, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26756099

RESUMEN

PURPOSE: To correlate 18F-FDG uptake on PET/CT with patterns of arterial and portal perfusion on multi-detector CT (MDCT) in patients with hepatocellular carcinoma (HCC) and to assess the value of variables from PET/CT and MDCT in predicting histological grades and overall survival. METHODS: We retrospectively analyzed MDCT and PET/CT of 66 patients with HCC who underwent surgical treatment. Tumor peak standard uptake value (SUV) was divided by the mean liver SUV (T/LSUV). The mean tumor Hounsfield unit (HU) to mean liver HU was calculated for arterial (T/LHU-A) and portal phases (T/LHU-P). All patients were divided into three groups: I, T/LHU-A ≤l and T/LHU-P <1; II, T/LHU-A >1 and T/LHU-P <1; and III, T/LHU-A >1 and T/LHU-P ≥1. The relationships between the CT perfusion groups and T/LSUV were assessed. Multivariate logistic regression analyses were performed using clinical and imaging parameters for predicting histological grade. Overall survival curves stratified by T/LSUV and CT perfusion groups were estimated using the Kaplan-Meier method. RESULTS: Statistically significant differences in T/LSUV were noted between groups I and II (2.29 [range 1.74-3.60] vs. 1.20 [range 1.07-1.58], P < 0.001) and groups I and III (2.29 [range 1.74-3.60] vs. 1.30 [range 1.07-1.43], P < 0.001). In multivariate analysis, a T/LSUV cutoff of >1.46 was the only independent predictor of tumor grade, with an odds ratio of 8.462 (95% confidence interval 1.799-39.803). Kaplan-Meier curves showed significant differences in OS according to T/LSUV >1.62, group I perfusion pattern, and T/LSUV >1.62 plus group I perfusion pattern (P = 0.04, P = 0.021, and P = 0.002, respectively). CONCLUSION: 18F-FDG PET/CT is not commonly used for detecting HCC due to its limited sensitivity. We found that increased 18F-FDG uptake is associated with decreased arterial and portal perfusion on MDCT. This can be used to preselect patients who would benefit the most from PET/CT. Meanwhile, 18F-FDG uptake remained as the only independent predictor of histological grade, and higher 18F-FDG uptake and lower perfusion pattern on MDCT were significantly related to shorter OS.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Neoplasias Hepáticas/diagnóstico por imagen , Imagen de Perfusión , Sistema Porta/diagnóstico por imagen , Tomografía de Emisión de Positrones , Radiofármacos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen Multimodal , Tomografía Computarizada por Rayos X
15.
Pediatr Radiol ; 45(2): 188-93, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25030221

RESUMEN

BACKGROUND: Iterative reconstruction can be helpful to reduce radiation dose while maintaining image quality. However, this technique has not been fully evaluated in children during abdominal CT. OBJECTIVE: To compare objective and subjective image quality between half-dose images reconstructed with iterative reconstruction at iteration strength levels 1 to 5 (half-S1 to half-S5 studies) and full-dose images reconstructed with filtered back projection (full studies) in pediatric abdominal CT. MATERIALS AND METHODS: Twenty-one children (M:F = 13:8; mean age 8.2 ± 5.7 years) underwent dual-source abdominal CT (mean effective dose 4.8 ± 2.1 mSv). The objective image quality was evaluated as noise. Subjective image quality analysis was performed comparing each half study to the full study for noise, sharpness, artifact and diagnostic acceptability. RESULTS: Both objective and subjective image noise decreased with increasing iteration strength. Half-S4 and -S5 studies showed objective image noise similar to or lower than that of full studies. The half-S2 and -S3 studies produced the greatest sharpness and the half-S5 studies were the worst from a blocky appearance. Full and half studies did not differ in artifacts. Half-S3 studies showed the best diagnostic acceptability. CONCLUSION: Half-S4 and -S5 studies objectively and half-S3 studies subjectively showed comparable image quality to full studies in pediatric abdominal CT.


Asunto(s)
Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adolescente , Artefactos , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Fantasmas de Imagen , Radiografía Abdominal , Estudios Retrospectivos
16.
Chemistry ; 19(30): 9795-9, 2013 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-23765591

RESUMEN

Spiro compounds: An iodine monochloride-induced intramolecular cyclization of 1-[4'-methoxy(1,1'-biphenyl)2-yl]alkynones has been developed (see scheme). An electrophilic iodocyclization selectively takes place at the ipso position (versus the ortho electrophilic aromatic substitution) to afford 4'H-spiro(cyclohexa[2,5]diene-1,1'-naphthalene)-4,4'-diones, a new group of spiroconjugated compounds.

17.
J Vasc Surg ; 57(5): 1311-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23357520

RESUMEN

OBJECTIVE: The primary purpose of the current study was to evaluate the safety and effectiveness of selective coverage of the left subclavian artery (LSCA) without revascularization during thoracic endovascular aortic repair (TEVAR) in patients with bilateral patent vertebrobasilar junctions. The secondary purpose was to assess morphologic change of the vertebral artery (VA) after the procedure. METHODS: Among 126 patients who underwent TEVAR between 2006 and 2011, 29 patients requiring LSCA coverage without preemptive revascularization were retrospectively analyzed in this study. The patients were a mean age of 63.1 years (range, 45-84 years). The mean follow-up period was 19.9 months (range, 1-63 months). Bilateral patent vertebrobasilar junctions were evaluated by contrast-enhanced computed tomography (CT), time-of flight magnetic resonance angiography, or conventional angiography. Neurologic complications, such as spinal cord ischemia (SCI) or cerebrovascular accidents, were analyzed. Preprocedural and postprocedural changes in VAs were evaluated on follow-up contrast-enhanced CT. RESULTS: The overall 30-day mortality was 6.9% (2 of 29). None of the patients had SCI or a stroke of posterior circulation alone. Cerebrovascular accidents from embolic infarctions occurred in two patients (7.4%). Transient left arm ischemic symptoms were present in five patients (18.5%), but none required secondary interventions. Delayed development of type I endoleak occurred due to stent deformity in one patient, who underwent surgery. One patient required reintervention after the 10-month follow-up contrast-enhanced CT showed a pseudoaneurysm had developed at the distal margin of the previously placed stent graft. Hypertrophy of the right VA after TEVAR was seen in seven of 27 patients (25.9%); two patients showed bilateral hypertrophy of VAs. CONCLUSIONS: LSCA coverage without revascularization can be safely performed during TEVAR in patients with bilateral patent vertebrobasilar junctions. Hypertrophy of the right VA was noted in 25.9% of patients after LSCA coverage.


Asunto(s)
Aorta Torácica/cirugía , Enfermedades de la Aorta/cirugía , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Arteria Subclavia/cirugía , Grado de Desobstrucción Vascular , Arteria Vertebral/fisiopatología , Anciano , Anciano de 80 o más Años , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/fisiopatología , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/mortalidad , Enfermedades de la Aorta/fisiopatología , Aortografía/métodos , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/mortalidad , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/terapia , Diseño de Prótesis , Estudios Retrospectivos , Stents , Arteria Subclavia/diagnóstico por imagen , Arteria Subclavia/fisiopatología , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Arteria Vertebral/diagnóstico por imagen
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