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1.
Environ Res ; 212(Pt A): 113217, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35381261

RESUMEN

In this study, the effect of the use of heat-not-burn (HnB) products on indoor air quality (IAQ) was evaluated. To do this, the concentrations of nicotine, propylene glycol (PG), and vegetable glycerin (VG) directly emitted when using HnB products were analyzed and compared to those from conventional cigarettes. Furthermore, the levels of VOCs, aldehydes, nanoparticle, and particulate matter (PM) detected when subjects used HnB products in the exposure chamber were evaluated the effect on IAQ. As a result, the range of nicotine levels transferred by HnB products (0.8-1.2 mg cigarette-1) is lower than that by conventional cigarettes (2.4-3.6 mg cigarette-1). On the other hand, the range of VG levels emitted from HnB products (3.1-5.9 mg cigarette-1) were higher than that emitted from conventional cigarettes (0.6-3.0 mg cigarette-1). In addition, although the amount generated from HnB products was small compared to those from conventional cigarettes, various kinds of VOCs, aldehydes, nanoparticle and PM were produced, and these were confirmed to affect IAQ.


Asunto(s)
Contaminación del Aire Interior , Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Aldehídos , Calor , Humanos , Nicotina/análisis , Material Particulado/análisis , Verduras
2.
Nanotechnology ; 32(50)2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34044379

RESUMEN

Semiconductor p-n junctions are essential building blocks of electronic and optoelectronic devices. Although vertical p-n junction structures can be formed readily by growing in sequence, lateral p-n junctions normal to surface direction can only be formed on specially patterned substrates or by post-growth implantation of one type of dopant while protecting the oppositely doped side. In this study, we report the monolithic formation of lateral p-n junctions in GaAs nanowires (NWs) on a planar substrate sequentially through the Au-assisted vapor-liquid-solid selective lateral epitaxy using metalorganic chemical vapor deposition. p-type and n-type segments are formed by modulating the gas phase flow of p-type (diethylzinc) and n-type (disilane) precursorsin situduring nanowire growth, allowing independent sequential control of p- and n-doping levels self-aligned in-plane in a single growth run. The p-n junctions formed are electrically characterized by fabricating arrays of p-n junction NW diodes with coplanar ohmic metal contacts and two-terminalI-Vmeasurements. The lateral p-n diode exhibits a 2.15 ideality factor and a rectification ratio of ∼106. The electron beam-induced current measurement confirms the junction position. The extracted minority carrier diffusion length is much higher compared to those previously reported, suggesting a low surface recombination velocity in these lateral NWp-n diodes.

3.
Biol Pharm Bull ; 41(10): 1606-1610, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30270331

RESUMEN

ß-Escin, a natural triterpene saponin was extracted from Aesculus hippocastanum seeds, which have been widely used to treat inflammation in traditional medicine. In an effort to study the possible anti-tumor effects of ß-escin, we performed wound healing, invasion, and adhesion assays to examine the effects of ß-escin on cell migration, invasion, and angiogenesis. Our results revealed that ß-escin inhibits cell migration as well as motility in B16F10 and SK-MEL5 cells in a dose-dependent manner. RT-PCR and Western blot analysis showed that ß-escin increased TIMP-1, -2 while significantly downregulated phosphorylated extracellular signal-regulated kinase (p-ERK) expression, and suppressing nuclear factor-kappa B (NF-κB) and inhibitor of nuclear factor-kappa B (IκB) expression. Overall, the data from the current study suggest that ß-escin has the potential for inhibiting both metastatic and angiogenic activities, and are the earliest evidence for the involvement of the NF-κB/IκB signaling in ß-escin-induced anti-tumor effects.


Asunto(s)
Aesculus/química , Escina/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Sistema de Señalización de MAP Quinasas , Melanoma/metabolismo , FN-kappa B/metabolismo , Extractos Vegetales/farmacología , Animales , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación hacia Abajo , Escina/uso terapéutico , Humanos , Proteínas I-kappa B/metabolismo , Melanoma/tratamiento farmacológico , Ratones , Fosforilación , Fitoterapia , Extractos Vegetales/uso terapéutico , Semillas , Transducción de Señal
4.
Biochim Biophys Acta ; 1852(12): 2662-70, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26410577

RESUMEN

Alcohol consumption exacerbates alcoholic liver disease by attenuating the activity of AMP-activated protein kinase (AMPK). AMPK is activated by fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, and inhibited by direct interaction with cereblon (CRBN), a component of an E3 ubiquitin ligase complex. Based on these preliminary findings, we investigated that CRBN would be up-regulated in the liver by alcohol consumption and that CRBN deficiency would ameliorate hepatic steatosis and pro-inflammatory responses in alcohol-fed mice by increasing AMPK activity. Wild-type, CRBN and PPARα null mice were fed an alcohol-containing liquid diet and administered with fenofibrate. Gene expression profiles and metabolic changes were measured in the liver and blood of these mice. Expression of CRBN, cytochrome P450 2E1 (CYP2E1), lipogenic genes, pro-inflammatory cytokines, serum alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were increased in the Lieber-DeCarli alcohol-challenged mice. Fenofibrate attenuated the induction of CRBN and reduced hepatic steatosis and pro-inflammatory markers in these mice. Ablation of the gene encoding CRBN produced the same effect as fenofibrate. The increase in CRBN gene expression by alcohol and the reduction of CRBN expression by fenofibrate were negated in PPARα null mice. Fenofibrate increased the recruitment of PPARα on CRBN gene promoter in WT mice but not in PPARα null mice. Silencing of AMPK prevented the beneficial effects of fenofibrate. These results demonstrate that activation of PPARα by fenofibrate alleviates alcohol-induced hepatic steatosis and inflammation by reducing the inhibition of AMPK by CRBN. CRBN is a potential therapeutic target for the alcoholic liver disease.

5.
Nano Lett ; 14(12): 6836-41, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25343224

RESUMEN

The recently emerged selective lateral epitaxy of semiconductor planar nanowires (NWs) via the vapor-liquid-solid (VLS) mechanism has redefined the long-standing symbolic image of VLS NW growth. The in-plane geometry and self-aligned nature make these planar NWs completely compatible with large scale manufacturing of NW-based integrated nanoelectronics. Here, we report on the realization of perfectly site-controlled growth of GaAs planar NW arrays with unity yield using lithographically defined gold (Au) seed dots. The growth rate of the planar NWs is found to decrease with the NW width at fixed spacing, which is consistent with the conventional VLS model based on the Gibbs-Thomson effect. It is found that in general, the planar and out-of-plane NW growth modes are both present. The yield of planar NWs decreases as their lateral dimension shrinks, and 100% yield of planar NWs can be achieved at moderate V/III ratios. Based on a study of the shape of seed particles, it is proposed that the adhesion between the liquid-phase seed particle and the substrate surface is important in determining the choice of growth mode. These studies represent advances in the fundamental understanding of the VLS planar NW growth mechanism and in the precise control of the planar NW site, density, width, and length for practical applications. In addition, high quality planar InAs NWs on GaAs (100) substrates is realized, verifying that the planar VLS growth mode can be extended to heteroepitaxy.

6.
Phys Eng Sci Med ; 47(2): 443-451, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38224383

RESUMEN

With the increasing use of flattening filter free (FFF) beams, it is important to evaluate the impact on the skin dose and target coverage of breast cancer treatments. This study aimed to compare skin doses of treatments using FFF and flattening filter (FF) beams for breast cancer. The study established treatment plans for left breast of an anthropomorphic phantom using Halcyon's 6-MV FFF beam and TrueBeam's 6-MV FF beam. Volumetric modulated arc therapy (VMAT) with varying numbers of arcs and intensity modulated radiation therapy (IMRT) were employed, and skin doses were measured at five points using Gafchromic EBT3 film. Each measurement was repeated three times, and averaged to reduce uncertainty. All plans were compared in terms of plan quality to ensure homogeneous target coverage. The study found that when using VMAT with two, four, and six arcs, in-field doses were 19%, 15%, and 6% higher, respectively, when using Halcyon compared to TrueBeam. Additionally, when using two arcs for VMAT, in-field doses were 10% and 15% higher compared to four and six arcs when using Halcyon. Finally, in-field dose from Halcyon using IMRT was about 1% higher than when using TrueBeam. Our research confirmed that when treating breast cancer with FFF beams, skin dose is higher than with traditional FF beams. Moreover, number of arcs used in VMAT treatment with FFF beams affects skin dose to the patient. To maintain a skin dose similar to that of FF beams when using Halcyon, it may be worth considering increasing the number of arcs.


Asunto(s)
Neoplasias de la Mama , Aceleradores de Partículas , Fantasmas de Imagen , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada , Piel , Humanos , Piel/efectos de la radiación , Femenino , Neoplasias de la Mama/radioterapia , Mama/efectos de la radiación , Mama/diagnóstico por imagen , Planificación de la Radioterapia Asistida por Computador , Relación Dosis-Respuesta en la Radiación , Dosis de Radiación
7.
Chemosphere ; 328: 138611, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37023905

RESUMEN

Tunnels are the preferred experimental environments for estimating vehicle emission factors (EFs) under real-world driving conditions. In this study, online measurements of traffic-related air pollutants (including CO2, NOX, SO2, O3, particulate matter [PM], and volatile organic compounds [VOCs]) were conducted using a mobile laboratory in the Sujungsan Tunnel in Busan, Korea. Mobile measurements generated concentration profiles of the target exhaust emissions inside the tunnel. These data were used to produce a zonation of the tunnel, i.e., mixing and accumulation zones. There were differences between the CO2, SO2, and NOX profiles, and a starting point that was free from ambient air mixing effects could be set at 600 m from the tunnel entrance. The EFs of vehicle exhaust emissions were calculated using pollutant concentration gradients. The average EFs for CO2, NO, NO2, SO2, PM10, PM2.5, and ∑VOCs were 149,000, 380, 55, 29.2, 9.64, 4.33, and 16.7 mg km-1·veh-1, respectively. Among the VOC groups, alkanes contributed more than 70% of the VOC EF. Mobile measurement-derived EFs were validated using the conventional EFs from stationary measurements. The EF results from the mobile measurements matched those from the stationary measurements, while the absolute concentration differences between them implied complex aerodynamic movements of the target pollutants inside the tunnel. This study demonstrated the usefulness and advantages of applying mobile measurements in a tunnel environment and indicated the potential of the approach for observation-based policymaking.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Ambientales , Compuestos Orgánicos Volátiles , Emisiones de Vehículos/análisis , Contaminantes Atmosféricos/análisis , Compuestos Orgánicos Volátiles/análisis , Dióxido de Carbono , Monitoreo del Ambiente/métodos , Material Particulado/análisis
8.
Radiat Oncol J ; 41(3): 199-208, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37793629

RESUMEN

PURPOSE: An optimal once-daily radiotherapy (RT) regimen is under investigation for definitive concurrent chemoradiotherapy (CCRT) in limited disease small cell lung cancer (LD-SCLC). We compared the efficacy and safety of dose escalation with intensity-modulated radiotherapy (IMRT). MATERIALS AND METHODS: Between January 2016 and March 2021, patients treated with definitive CCRT for LD-SCLC with IMRT were retrospectively reviewed. Patients who received a total dose <50 Gy or those with a history of thoracic RT or surgery were excluded. The patients were divided into two groups (standard and dose-escalated) based on the total biologically effective dose (BED, α/ß = 10) of 70 Gy. The chemotherapeutic regimen comprised four cycles of etoposide and cisplatin. RESULTS: One hundred and twenty-two patients were analyzed and the median follow-up was 27.8 months (range, 4.4 to 76.9 months). The median age of the patients was 63 years (range, 35 to 78 years) and the majority had a history of smoking (86.0%). The 1- and 3-year overall survival rates of the escalated dose group were significantly higher than those of the standard group (93.5% and 50.5% vs. 76.7% and 33.3%, respectively; p = 0.008), as were the 1- and 3-year freedom from in-field failure rates (91.4% and 66.5% vs. 73.8% and 46.9%, respectively; p = 0.018). The incidence of grade 2 or higher acute and late pneumonitis was not significantly different between the two groups (p = 0.062, 0.185). CONCLUSION: Dose-escalated once-daily CCRT with IMRT led to improved locoregional control and survival, with no increase in toxicity.

9.
Sci Total Environ ; 893: 164892, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37327901

RESUMEN

In urban areas, particulate matter emitted from vehicles directly affects the health of citizens near roads. Thus, in this study, particle size distribution was measured by the horizontal and vertical distances along a highway road with heavy traffic to characterize the dispersion phenomena of particulate matter emitted from vehicles. In addition, the contribution of pollution sources was analyzed using a source-receptor model. A concentration gradient was observed in which the concentration decreased with the increase in the distance from the road when the wind blew from the road to the monitoring locations. The concentration was slightly higher within 50 m of the road when the wind blows parallel to the road, and similar concentrations were found at the other monitoring locations further away from the roads. In particular, the higher the turbulence intensity of the wind, the lower is the concentration gradient coefficient because of the more enhanced mixing and dispersion. A positive matrix factorization (PMF) model with the measured particle size distribution data in the range of 9-300 nm resulted in a contribution of about 70 % (number) and 20 % (mass) to particle concentrations because of six types of vehicles including LPG, two gasoline vehicles (GDI, MPI), and three diesel vehicles with 3rd, 4th, and 5th emission classes. It showed a decrease in the vehicular contribution as the distance from the road increased. Particle number concentrations decreased with increasing altitude up to 30 m above the ground. The results of this study can be useful in deriving generalized gradient equations of particle concentrations exposed by distance and wind direction at the roadside using traffic and meteorological conditions and for establishing environmental policies, such as roadside exposure assessment, in the future. A CAPSULE ABSTRACT: Dispersion of particles emitted from vehicles on a busy highway was characterized by roadside measurements of horizontal and vertical profiles of particle size distributions measured at four locations. The source profiles and contributions were estimated by major sources using a source-receptor model such as PMF.

10.
ACS Appl Mater Interfaces ; 13(9): 11177-11184, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33646764

RESUMEN

Achieving large scale precise positioning of the vapor-liquid-solid (VLS) nanowires is one of the biggest challenges for mass production of nanowire-based devices. Although there have been many noteworthy progresses in postgrowth nanowire alignment method development over the past few decades, these methods are mostly suitable for low density applications only. For high density applications such as transistors, both high yield and density are required. Here, we report an elastocapillary force-induced nanowire-aligning method that is extremely simple, clean, and can achieve single/multiple nanowire arrays with up to 98.8% yield and submicron pitch between the nanowires.

11.
Sci Total Environ ; 658: 1549-1558, 2019 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-30678013

RESUMEN

Pollutants in tailpipe emissions can be highly elevated around roadways, and in early mornings the pollution plume can extend hundreds of meters into surrounding neighborhoods. Solid sound walls and vegetation barriers are commonly used to mitigate noise, but they also help mitigate near-road air pollution. Here we assess the effectiveness of barriers consisting of vegetation only and of a combination of vegetation and a solid sound wall (combination barrier) in reducing pollution concentrations downwind of roads, under stable atmospheric stability and calm to light wind conditions. Because there was no practical (no barrier) control site in the area, we primarily compare the two barrier types to each other and explore the importance of atmospheric conditions. Using measurements collected with a mobile platform, we develop concentration decay profiles of ultrafine and fine particles, oxides of nitrogen (NO and NO2) and carbon monoxide downwind of a freeway in California with different barrier configurations and meteorological conditions. Diurnally averaged data collected with passive samplers indicate that pollution from morning rush hour has about equal impact as the entire remainder of the day, because of differences in atmospheric dispersion as the day progresses. Under calm and stable atmospheric conditions (wind speed <0.6 m/s); a vegetation-only barrier was more effective than a combination barrier with a total height that was somewhat lower than the vegetation-only barrier, by 10-24% in the first 160 m downwind. Under light winds (above ~ 0.6 but below 3 m/s) and stable conditions, the combination barrier was more effective than the vegetation barrier alone, by 6-33%, in the first 160 m from the barrier. The average particle size downwind of the vegetation-only barrier was larger than downwind of the combination barrier, indicating that particle deposition plays an important role in the reductions observed downwind of vegetation. Our results are consistent with the notion that at low wind speeds, vegetation acts as an effective barrier. Overall, adding vegetation alone or to an existing solid barrier results in lower downwind pollution concentrations, especially under low wind speeds when concentrations can be high.


Asunto(s)
Contaminantes Atmosféricos/análisis , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente , Emisiones de Vehículos/análisis , Contaminación del Aire/análisis , California , Tamaño de la Partícula , Material Particulado/análisis , Viento
12.
Radiat Oncol ; 14(1): 116, 2019 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-31272506

RESUMEN

BACKGROUND: Systemic inflammation plays a critical role in cancer progression and oncologic outcomes in cancer patients. We investigated whether preoperative inflammatory biomarkers, including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and neutrophil to lymphocyte ratio (NLR), could be surrogate biomarkers for predicting overall survival (OS) in soft tissue sarcoma (STS) patients treated with surgery and postoperative radiotherapy. METHODS: A series of 99 patients who presented with localized extremity STS were retrospectively reviewed. The preoperative CRP levels, ESR, and NLR were evaluated for associations with OS, disease-free survival (DFS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS). Cutoff values for CRP, ESR, and NLR were derived from receiver-operating characteristic curve analysis. RESULTS: Elevated CRP (> 0.14 mg/dL), ESR (> 15 mm/h), and NLR (> 1.95) levels were seen in 33, 44, and 45 patients, respectively. Of these three inflammatory biomarkers, elevated CRP and ESR were associated with a poorer OS (CRP: P = 0.050; ESR: P = 0.001), DFS (CRP: P = 0.023; ESR: P = 0.003), and DMFS (CRP: P = 0.015; ESR: P = 0.001). By multivariate analysis, an elevated ESR was found to be an independent prognostic factor for OS (HR 3.580, P = 0.025) and DMFS (HR 3.850, P = 0.036) after adjustment for other established prognostic factors. CONCLUSIONS: The preoperative ESR level is a simple and useful surrogate biomarker for predicting survival outcomes in STS patients and might improve the identification of high-risk patients of tumor relapse in clinical practice.


Asunto(s)
Sedimentación Sanguínea/efectos de la radiación , Extremidades/efectos de la radiación , Extremidades/cirugía , Recurrencia Local de Neoplasia/mortalidad , Radioterapia Adyuvante/mortalidad , Sarcoma/mortalidad , Procedimientos Quirúrgicos Operativos/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/terapia , Pronóstico , Curva ROC , Estudios Retrospectivos , Sarcoma/patología , Sarcoma/terapia , Tasa de Supervivencia , Adulto Joven
14.
Oncol Rep ; 19(6): 1399-403, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18497943

RESUMEN

The plant Geum japonicum Thunberg (GjT) has been used as a diuretic in traditional medicine. Herein, we report that the GjT extract blocks both the spread of human umbilical vein endothelial cells (HUVECs) on matrigel and the migration of B16 cells. We used various assays to test for cell attachment, spreading, wound healing and angiogenesis. A reverse transcription-polymerase chain reaction (RT-PCR) and a mitogen-activated protein kinase (MAPK) assay were also carried out for the mechanistic study of GjT. Our results showed that a fraction of methylene chloride fraction from GjT inhibited B16 cells during cell attachment and migration and suppressed tube formation in a dose-dependent manner. An RT-PCR analysis showed that the methylene chloride extract decreased the mRNA expression of CD44 and TIMP-2. A Western blot analysis of the phosphorylation of MAPK kinases (ERK, JNK and p38) showed that the GjT fraction increased the expression of phospho-JNK, suggesting that GjT has the potential to alleviate metastatic and angiogenic activity, via a phospho-JNK signaling pathway.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Geum/química , Melanoma Experimental/irrigación sanguínea , Cloruro de Metileno/farmacología , Neovascularización Patológica/tratamiento farmacológico , Animales , Western Blotting , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Endotelio Vascular/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Fosforilación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Venas Umbilicales/citología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
15.
Phytother Res ; 22(9): 1195-9, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18697182

RESUMEN

Piperlongumine, a pyridone alkaloid isolated from Piper longum L., exhibited a potential inhibitory effect on washed rabbit platelet aggregation induced by collagen, arachidonic acid (AA) and platelet activating factor (PAF), without any inhibitory effect on that induced by thrombin. Piperlongumine was used as a lead compound for the synthesis of new antiplatelet agents. Seven synthetic compounds were newly synthesized from 3,4,5-trimethoxycinnamic acid (TMCA). They were 1-piperidin-1-yl-3-(3,4,5-trimethoxy-phenyl)prop-2-en-1-one (1'), 1-morpholin-4-yl-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (2'), 1-(3,5-dimethylpiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (3'), 1-(2-methylpiperidin-1-yl)-3-(3,4,5-tri-methoxyphenyl)prop-2-en-1-one (4'), 1-(3-hydroxypiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)- prop-2-en-1-one (5'), 1-[3-(3,4,5-tri-methoxyphenyl) acryloyl]-piperidin-2-one (6') and ethyl 1-[3-(3,4,5-trimethoxyphenyl)-acryloyl]piperidine-4-carboxylate (7'). Among those seven synthetic derivatives, 1-(3,5-dimethylpiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (3') had the most inhibitory effect on platelet aggregation induced by collagen, AA and PAF.


Asunto(s)
Dioxolanos/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Animales , Dioxolanos/química , Técnicas In Vitro , Masculino , Inhibidores de Agregación Plaquetaria/química , Conejos , Análisis Espectral/métodos
16.
Environ Pollut ; 233: 235-245, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29096296

RESUMEN

Epidemiological studies have shown that exposure to traffic-related pollutants increases incidence of adverse health outcomes. Transit users in cities across the globe commonly spend 15-45 min or more waiting at transit stops each day, often at locations with high levels of pollution from traffic. Here, we investigate the characteristics of concentration profiles of ultrafine particles (UFP) with 5 m spatial resolution across intersections, to determine the best place to site transit stops to minimize exposures. Cross-intersection UFP profiles were derived from 1744 profiles covering 90 m before and after each intersection center with a mobile monitoring platform. Measurements were made at 10 signalized intersections located at six urban sites, each with a distinct built environment, during both mornings and afternoons. Measurements were made within 1.5 m of the sidewalk and approximately at breathing height (1.5 m above ground level) to approximate sidewalk exposures. UFP profiles were strongly influenced by high emissions from vehicle stops and accelerations, and peaked within 30 m of intersection centers; from there concentrations decreased sharply with distance. Peak concentrations averaged about 90% higher than the minima along the block. They were accompanied by more frequent and larger transient concentration spikes, increasing the chance of people near the intersection being exposed to both short-term extremely high concentration spikes and higher average concentrations. The decays are somewhat larger before the intersection than after the intersection, however as siting transit stops after intersections is preferred for smooth traffic flow, we focus on after the intersection. Simple time-duration exposure calculations combined with breathing rates suggest moving a bus stop from 20 to 40-50 m after the intersection can reduce transit-users' exposure levels to total UFP substantially, in proportion to the reciprocal of the magnitude of elevation at the intersection.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Transportes/estadística & datos numéricos , Emisiones de Vehículos/análisis , Ciudades , Planificación de Ciudades/métodos , Humanos , Peatones , Transportes/métodos
17.
Clin Lung Cancer ; 19(2): e253-e261, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29196082

RESUMEN

INTRODUCTION: The purpose of this study was to assess the effect of dose escalation of stereotactic ablative radiotherapy (SABR) by investigating the long-term clinical outcomes of SABR for stage I non-small-cell lung cancer (NSCLC). METHODS: A retrospective analysis was performed on a total of 169 patients with 178 lesions of stage I NSCLC treated with SABR at a single institution from June 2000 to May 2015. The standard dose scheme for SABR was 48 Gy in 4 fractions during the early period of the analysis, but it was escalated to 60 Gy in 4 fractions from June 2009. All failures were recorded over the follow-up period. RESULTS: Median follow-up time was 32 months. The 5-year overall survival rate was 46.7%, and the actuarial local control rate was 79.3%. Tumor size was an independent prognostic factor for survival. No relapse occurred in tumors ≤ 2 cm irrespective of SABR dose. Escalated doses of approximately 60 Gy in 4 fractions (biologically effective dose [BED] = 150 Gy10) achieved higher local control compared with 48 Gy in 4 fractions (BED = 106 Gy10) (76.2% vs. 60.6%) at 5-year follow-up (P = .022) in tumors > 2 cm. There were no differences in treatment-related toxicities between the dose groups. Major failures consisted of distant metastasis to another lung parenchyma. CONCLUSION: SABR provides satisfactory long-term local control and high overall survival in medically inoperable stage I NSCLC. Tumors ≤ 2 cm had no local recurrence regardless of dose; whereas for tumors > 2 cm, an escalated BED of approximately 150 Gy10 provided significantly higher local tumor control.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Radiocirugia , Carga Tumoral , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Radiocirugia/efectos adversos , Efectividad Biológica Relativa , República de Corea , Estudios Retrospectivos , Tasa de Supervivencia
18.
Oncol Rep ; 18(4): 849-53, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17786345

RESUMEN

Gastrodia elata Blume (GEB) is an important medicinal plant in Korea. In order to confirm the anti-tumor activities of GEB extracts, we carried out various in vitro anti-tumor assays, including a wound assay and an invasion assay using an ethyl ether extract of GEB. The results showed that the GEB extract exhibits potent anti-tumor activity in vitro in a dose-dependent manner. The expression of CD44, cdc42, Timp-2 or RhoA mRNA did not change by GEB treatment, compared to that of the control. GTP-Ras, an active form of a G-coupled protein family, however, is associated with the anti-tumor activity of GEB extracts. We examined various molecular markers related to metastasis by reverse transcriptase-polymerase chain reaction with the extract of GEB-treated B16 cells. There was an increase in GTP-Ras expression by the Gastrodia elata Blume extract. Together, these results suggest that the Gastrodia elata Blume extract could have potential in alleviating tumorigenesis, by a GTP-Ras-dependent pathway; although the precise molecular mechanisms are still being examined.


Asunto(s)
Gastrodia/química , Melanoma Experimental/tratamiento farmacológico , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos , Proteínas ras/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Animales , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Colágeno , Combinación de Medicamentos , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Laminina , Medicina Tradicional de Asia Oriental , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Invasividad Neoplásica/patología , Fitoterapia , Proteoglicanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Inhibidor Tisular de Metaloproteinasa-2/genética , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Venas Umbilicales/citología , Venas Umbilicales/efectos de los fármacos , Venas Umbilicales/metabolismo , Cicatrización de Heridas/efectos de los fármacos , Proteína de Unión al GTP cdc42/genética , Proteína de Unión al GTP cdc42/metabolismo , Proteínas ras/genética , Proteína de Unión al GTP rhoA/genética
19.
J Antibiot (Tokyo) ; 70(11): 1065-1069, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28874849

RESUMEN

In many pathogenic Gram-negative bacteria, such as Salmonella, Escherichia coli, Yersinia and Chlamydia spp., which cause diseases in humans, the type III secretion system (TTSS) is an important virulence factor that translocates effector proteins into the cytosol of host cells. Thus, the TTSS is a good target for antibacterial agents. Here we used a hemolysis assay to search for TTSS inhibitors and found that a compound from Magnolia obovata called obovatol blocks the TTSS of Salmonella. Obovatol showed potent inhibitory activity (IC50=19.8 µM) against the TTSS-related hemolysis of Salmonella, which was not due to a reduction of bacterial growth. Instead, the compound inhibited bacterial motility, TTSS-related mRNA expression and effector protein secretion. These data demonstrate the inhibitory effect of obovatol on the Salmonella TTSS and suggest that it could be useful for the prevention and supplementary treatment of bacterial infections.


Asunto(s)
Compuestos de Bifenilo/farmacología , Magnolia/química , Éteres Fenílicos/farmacología , Salmonella/patogenicidad , Sistemas de Secreción Tipo III/efectos de los fármacos , Antibacterianos/administración & dosificación , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Compuestos de Bifenilo/administración & dosificación , Compuestos de Bifenilo/aislamiento & purificación , Hemólisis/efectos de los fármacos , Concentración 50 Inhibidora , Éteres Fenílicos/administración & dosificación , Éteres Fenílicos/aislamiento & purificación
20.
Anticancer Res ; 37(8): 4239-4246, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28739713

RESUMEN

AIM: In the present study we assessed if postoperative radiotherapy (PORT) using conventional fractionation confers a benefit in cutaneous melanoma patients with lymph node (LN) metastasis. PATIENTS AND METHODS: Sixty-two patients with axillary or inguinal LN metastasis were retrospectively reviewed. Twenty-eight patients received PORT. The median RT dose was 50 Gy in 25 fractions. The high-risk group was defined by the presence of any of the following: ≥3 LNs, size ≥3 cm, extranodal extension. RESULTS: The median follow-up time was 34 months. PORT showed a significant benefit on 5-year axilla-inguinal recurrence-free survival (RFS) in high-risk patients (RT 100% vs. No-RT 37%, p=0.001). There was also a benefit of RT on 5-year out-field RFS in the high-risk population (RT 93% vs. No-RT 29%, p=0.002). There were no ≥grade 2 lymphedemas after RT. CONCLUSION: PORT using conventional fractionation for high-risk LN metastasis from cutaneous melanoma is feasible with comparable regional control and minimal toxicity.


Asunto(s)
Metástasis Linfática/radioterapia , Melanoma/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Radioterapia Adyuvante/efectos adversos , Neoplasias Cutáneas/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/efectos de la radiación , Ganglios Linfáticos/cirugía , Metástasis Linfática/patología , Masculino , Melanoma/patología , Melanoma/cirugía , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Cuidados Posoperatorios , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Resultado del Tratamiento , Melanoma Cutáneo Maligno
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