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1.
Mol Ecol ; 32(24): 6796-6808, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37888909

RESUMO

The dissolution of anthropogenic carbon dioxide (CO2 ) in seawater has altered its carbonate chemistry in the process of ocean acidification (OA). OA affects the viability of marine species. In particular, calcifying organisms and their early planktonic larval stages are considered vulnerable. These organisms often utilize energy reserves for metabolism rather than growth and calcification as supported by bulk RNA-sequencing (RNA-seq) experiments. Yet, transcriptomic profiling of a bulk sample reflects the average gene expression of the population, neglecting the variations between individuals, which forms the basis for natural selection. Here, we used single-embryo RNA-seq on larval sea urchin Heliocidaris crassispina, which is a commercially and ecologically valuable species in East Asia, to document gene expression changes to OA at an individual and family level. Three paternal half-sibs groups were fertilized and exposed to 3 pH conditions (ambient pH 8.0, 7.7 and 7.4) for 12 h prior to sequencing and oxygen consumption assay. The resulting transcriptomic profile of all embryos can be distinguished into four clusters, with differences in gene expressions that govern biomineralization, cell differentiation and patterning, as well as metabolism. While these responses were influenced by pH conditions, the male identities also had an effect. Specifically, a regression model and goodness of fit tests indicated a significant interaction between sire and pH on the probability of embryo membership in different clusters of gene expression. The single-embryo RNA-seq approach is promising in climate stressor research because not only does it highlight potential impacts before phenotypic changes were observed, but it also highlights variations between individuals and lineages, thus enabling a better determination of evolutionary potential.


Assuntos
Ouriços-do-Mar , Água do Mar , Humanos , Animais , Masculino , Água do Mar/química , Concentração de Íons de Hidrogênio , Ouriços-do-Mar/genética , Perfilação da Expressão Gênica , Larva/fisiologia , Transcriptoma/genética , Dióxido de Carbono/química , Oceanos e Mares
2.
Soft Matter ; 18(24): 4554-4564, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35674769

RESUMO

Electrically conducting nanospheres of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) with tailored size were prepared using a solvent displacement technique. To fabricate these nanostructures, dried PEDOT:PSS was dissolved in ethylene glycol (EG) and the solution was precipitated in deionized water. The proposed fabrication route allowed obtaining a water-based dispersion of PEDOT:PSS nanospheres with good optical properties. To determine the physical properties of the nanospheres, we followed a nanoscale approach, using atomic force microscopy. Our nanoscale mechanical and electrical investigations showed that the nanospheres retained good physical and conductivity properties, compared to the commercial product. Moreover, the local studies indicated that the reprecipitation process and the spherical shape lead to a different arrangement of the PSS and PEDOT phases.

3.
Macromol Rapid Commun ; 42(1): e2000654, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33283411

RESUMO

Over the past decades, polymer mechanochemistry has focused on the development and application of advanced force application methods to better understand the mechanochemical response of mechanophores. In this regard, techniques such as ultrasonication and single-molecule force spectroscopy (SMFS) are used to activate and detect up to thousands of chemical events within a polymer single chain, allowing the researchers to probe the mechanochemical reactivity of these stress-responsive motifs. Here, the most recent contributions of the single-molecule force spectroscopy technique to this field are presented, putting emphasis on the fundamental parameters of the technique for triggering specific force responses and on the description of force-extension curves measured for single- and multi-mechanophore polymers. Moreover, new contributions of microscopy-based techniques in the field of polymer mechanochemistry, as well as the potential application of single-chain nanoparticles as mechanoresponsive materials, are highlighted.


Assuntos
Nanopartículas , Polímeros , Fenômenos Mecânicos
4.
Environ Res ; 202: 111728, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34297937

RESUMO

BACKGROUND: Increased placental vascular resistance is a proposed mechanism by which air pollution exposure during pregnancy lowers birth weight and increases pregnancy-induced hypertensive disorders. OBJECTIVE: To examine the impact of acute air pollution exposure during pregnancy on uterine and umbilical artery Doppler indicators of placental vascular resistance. METHODS: After a first ultrasound to confirm gestational age, 2562 pregnant women recruited in 12 clinics throughout the United States underwent up to five standardized ultrasounds with Doppler measurements. Exposures to 11 air pollutants were estimated for the hour of ultrasound and each of the 2 h prior to ultrasound at the clinics using the National Air Quality Forecast Capability reanalysis products. We used mixed logistic regression to study the longitudinal odds ratio (OR) of any, uni- or bi-lateral systolic and diastolic uterine artery notching compared to no notching and the longitudinal OR of abnormal end diastolic flow of the umbilical artery compared to forward flow. Uterine and umbilical artery resistance indexes were studied using linear mixed models. RESULTS: Each inter-quartile range (IQR) increase of particulate matter < 2.5 µm, nitrate, ammonium, primary organic matter (POM) and nitrogen dioxide during the hour of ultrasound was associated with a decreased risk of unilateral systolic notch and with increased resistance index of the left uterine artery. For the umbilical artery, each IQR increase in ozone was associated with decreased resistance index (b: -0.26, 95 % CI: -0.52, -0.01) and with a decreased risk of abnormal end diastolic flow (OR: 0.36, 95 % CI: 0.14, 0.94); while each IQR increase of elemental carbon and POM was associated with increased risk of abnormal end diastolic flow (OR: 1.47, 95 % CI: 1.02, 2.13 and OR: 1.67, 95 % CI: 1.17, 2.39, respectively). DISCUSSION: Our results suggest acute air pollution exposure may influence placental vascular resistance.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Feminino , Desenvolvimento Fetal , Humanos , National Institute of Child Health and Human Development (U.S.) , Placenta/química , Placenta/diagnóstico por imagem , Gravidez , Artérias Umbilicais/química , Artérias Umbilicais/diagnóstico por imagem , Estados Unidos
5.
Atmos Environ (1994) ; 264: 118713, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34522157

RESUMO

In this work, we use observations and experimental emissions in a version of NOAA's National Air Quality Forecasting Capability to show that the COVID-19 economic slowdown led to disproportionate impacts on near-surface ozone concentrations across the contiguous U.S. (CONUS). The data-fusion methodology used here includes both U.S. EPA Air Quality System ground and the NASA Aura satellite Ozone Monitoring Instrument (OMI) NO2 observations to infer the representative emissions changes due to the COVID-19 economic slowdown in the U.S. Results show that there were widespread decreases in anthropogenic (e.g., NOx) emissions in the U.S. during March-June 2020, which led to widespread decreases in ozone concentrations in the rural regions that are NOx-limited, but also some localized increases near urban centers that are VOC-limited. Later in June-September, there were smaller decreases, and potentially some relative increases in NOx emissions for many areas of the U.S. (e.g., south-southeast) that led to more extensive increases in ozone concentrations that are partly in agreement with observations. The widespread NOx emissions changes also alters the O3 photochemical formation regimes, most notably the NOx emissions decreases in March-April, which can enhance (mitigate) the NOx-limited (VOC-limited) regimes in different regions of CONUS. The average of all AirNow hourly O3 changes for 2020-2019 range from about +1 to -4 ppb during March-September, and are associated with predominantly urban monitoring sites that demonstrate considerable spatiotemporal variability for the 2020 ozone changes compared to the previous five years individually (2015-2019). The simulated maximum values of the average O3 changes for March-September range from about +8 to -4 ppb (or +40 to -10%). Results of this work have implications for the use of widespread controls of anthropogenic emissions, particularly those from mobile sources, used to curb ozone pollution under the current meteorological and climate conditions in the U.S.

6.
J Environ Sci (China) ; 104: 150-168, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33985718

RESUMO

Using a bottom-up estimation method, a comprehensive, high-resolution emission inventory of gaseous and particulate atmospheric pollutants for multiple anthropogenic sectors with typical local sources has been developed for the Harbin-Changchun city agglomeration (HCA). The annual emissions for CO, NOx, SO2, NH3, VOCS, PM2.5, PM10, BC and OC during 2017 in the HCA were estimated to be 5.82 Tg, 0.70 Tg, 0.34 Tg, 0.75 Tg, 0.81Tg, 0.67 Tg, 1.59 Tg, 0.12 Tg and 0.26 Tg, respectively. For PM10 and SO2, the emissions from industry processes were the dominant contributors representing 54.7% and 49.5%, respectively, of the total emissions, while 95.3% and 44.5% of the total NH3 and NOx emissions, respectively, were from or associated with agricultural activities and transportation. Spatiotemporal distributions showed that most emissions (except NH3) occurred in November to March and were concentrated in the central cities of Changchun and Harbin and the surrounding cities. Open burning of straw made an important contribution to PM2.5 in the central regions of the northeastern plain during autumn and spring, while domestic coal combustion for heating purposes was significant with respect to SO2 and PM2.5 emissions during autumn and winter. Furthermore, based on Principal Component Analysis and Multivariable Linear Regression model, air temperature, relative humidity, electricity and energy consumption, and the urban and rural population were optimized to be representative indicators for rapidly assessing the magnitude of regional atmospheric pollutants in the HCA. Such indicators and equations were demonstrated to be useful for local atmospheric environment management.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Conservação dos Recursos Naturais , Monitoramento Ambiental , Humanos , Material Particulado/análise
7.
Diabetes Metab Res Rev ; 36(3): e3236, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31912598

RESUMO

AIMS: To compare disease remission rates, weight loss, and changes of metabolic parameters of patients after bariatric surgery with nonsurgical patients. METHODS: Based on the 2006-2017 Hospital Authority database, a population-based retrospective cohort of obese type 2 diabetes mellitus (T2DM) patients with and without bariatric surgery were identified. Surgical patients were matched with nonsurgical patients on 1-to-5 propensity score. Remission rates of diabetes, hypertension, and dyslipidaemia were reported annually up to 60 months. Changes in weight loss measurements (Body Mass Index [BMI], percentage of total weight loss [%TWL], percentage of excess weight loss [%EWL], and percentage of rebound in excess weight loss [%REWL]) and metabolic parameters (haemoglobin A1c [HbA1c ], systolic blood pressure [SBP], diastolic blood pressure [DBP], and low-density lipoprotein cholesterol [LDL-C]) were measured for both groups. RESULTS: Four hundred one surgical patients (310 restrictive surgeries; 91 bypass surgeries) and 1894 nonsurgical patients were included. Surgical patients had higher remission rates in diabetes and dyslipidaemia and better glycaemic control at 12 to 60 months (all Ps < .01). SBP and DBP were significantly lower for surgical group up to 12 months and similar between two groups after 12 months. Surgical patients had significantly lower BMI during follow-up period. %TWL and %EWL were higher in the surgery group (15.7% vs 3.7%; 48.8% vs 12.0%) at 60 months (P < .001); differences in %REWL between two groups were insignificant. The effectiveness of restrictive and bypass surgeries was similar at 60 months, although restrictive surgeries were slightly more effective in T2DM remission. CONCLUSIONS: Bariatric surgery was effective in weight loss, remission of diabetes, and dyslipidaemia in 5-year post-surgery.


Assuntos
Cirurgia Bariátrica , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/cirurgia , Obesidade/cirurgia , Redução de Peso/fisiologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Bases de Dados Factuais , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo , Pontuação de Propensão , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento
8.
Soft Matter ; 16(13): 3203-3208, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32154547

RESUMO

The effect of humidity on the ionic transport in the amorphous phase of poly(ethylene oxide) thin films has been studied by local dielectric spectroscopy. We explored a controlled humidity range between 15% RH and 50% RH. AFM-based local dielectric imaging allowed the thin film topography and the corresponding dielectric contrast maps to be obtained simultaneously. No humidity effect on the film topography was observed whereas large variation of the dielectric signal could be detected. In addition, we observed a clear dielectric contrast in different locations on the thin film surface. At selected regions with high contrast in the dielectric maps, we performed nanoDielectric Spectroscopy (nDS) measurements covering the frequency range from 5 Hz to 100 kHz. By modeling these spectroscopy results, we quantified the conductivity of the amorphous phase of the semicrystalline poly(ethylene oxide) films. The crystalline fraction of the PEO thin films was extracted and found to be about 36%, independently of humidity. However, the average conductivity increased by a factor of 25 from 2 × 10-10 to 5 × 10-9 S cm-1, by changing environmental humidity in the explored % RH range.

9.
Breast Cancer Res Treat ; 178(2): 401-408, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31432365

RESUMO

PURPOSE: Agents targeting the human epidermal growth factor receptor 2 (HER2) have improved outcomes of advanced HER2-positive breast cancer with durable responses. We evaluated first-line therapy long-term outcomes in patients responding for more than 1 year. METHODS: We retrospectively identified patients on first-line anti-HER2 therapy at The Royal Marsden Hospital for at least 1 year from 2001 to 2016. Demographics, disease characteristics, treatments and adverse events were recorded. Simple statistics, Fisher's, Chi squared and log-rank tests were used. RESULTS: 208 patients on treatment for at least 1 year had a median age of 54 years (31-88). 38.0% had de novo metastatic disease and 55.9% were ER positive. Of the relapsed cases, 54.4% previously had trastuzumab. At the time of presentation of metastatic disease, 27.4% of the entire cohort had pulmonary, 43.7% liver and 10.6% brain involvement. 97.1% received trastuzumab and 1.44% lapatinib; 33.2% pertuzumab and trastuzumab. 82.7% received chemotherapy (usually taxanes). 47.6% received maintenance endocrine therapy. Median progression-free survival was 39.5 months and overall survival 81.0 months. Overall response rate was 87.5%. Cardiotoxicity occurred in 4.8% of cases. Seven patients stopped treatment electively after 17-87 months and, so far, all remain in complete remission. CONCLUSIONS: First-line anti-HER2 treatment is associated with median overall survival longer than 6 years in half of the patients free from disease progression after a year, but most still relapse eventually. Response prediction would be key to inform trial design and treatment decisions in this setting.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/etiologia , Receptor ErbB-2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Terapia Combinada , Gerenciamento Clínico , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Receptor ErbB-2/metabolismo , Estudos Retrospectivos
10.
Eur Phys J E Soft Matter ; 42(7): 93, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31317340

RESUMO

Broadband dielectric spectroscopy (BDS) is a powerful technique that allows studying the molecular dynamics of materials containing polar entities. Among a vast set of different applications, BDS can be used as a complementary tool in polymer synthesis. In this work, we will show how BDS can be used to validate architectural features in Type-A polymers, those having a net dipole moment component along the chain contour. Specifically, we will focus on the evaluation of the dielectric relaxation of poly(glycidyl phenyl ether) (PGPE) samples designed and synthesized with a variety of topologies and regio-orders: linear regio-regular chains synthesized from monofunctional and bifunctional initiators, macrocyclic regio-regular chains, and linear and macrocyclic regio-irregular chains. Our study highlights the impact of using BDS as a complementary characterization technique for providing topological details of polymers, which are otherwise not possible with many traditional techniques (e.g., NMR and mass spectrometry).

11.
Dis Esophagus ; 31(13): 1, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30219909

RESUMO

BACKGROUND: Esophagectomy remains the mainstay treatment for esophageal cancer. Minimally invasive techniques have gained popularity in recent years. Whether minimally invasive methods result in equivalent or superior outcome to open esophagectomy or not is still controversial. The aim of the current study is to compare outcomes of minimally invasive and open esophagectomy from a single institution, using propensity score matching to lessen biases. METHODS: From 1994-2016, 724 patients with squamous cell cancer of the esophagus who underwent esophagectomy were studied. Data were retrieved from a prospectively collected database. Patients were divided into two groups: 453 had open esophagectomy (open group), and 271 had VATS esophagectomy with gastric mobilization either via laparotomy or laparoscopically (MIE group). A propensity score was generated for each patient based on age, gender, tumor level, use of neoadjuvant therapy, American Society of Anaesthesiologists (ASA) score, pathologic stage of disease, site of anastomosis, and residual tumour (R) categories and the two matched groups were compared in clinico-pathological features, morbidity and mortality rates, and long-term survival. All statistical calculations were performed with SPSS version 24 (SPSS, Chicago, IL). RESULTS: A total of 158 patients in MIE and 187 in open group are matched for comparison (1:3 matching). MIE resulted in less blood loss (220 vs 400ml, P < 0.001) but longer operative time (461 vs 305 mins, P < 0.001). Wound infection (3.7% vs 10.7%, P = 0.01) and respiratory complications (29% vs 55.1%, P < 0.001) were also less in MIE group. Except for a higher rate of conduit ischemia (6.3% vs 1.6%, P = 0.02), MIE had comparable surgical outcomes with open technique in rates of anastomotic leakage (5.7% vs 5.3%, P = 0.89), recurrent laryngeal nerve palsy (20.1% vs 18.7%, P = 0.10), reoperation (10.8% vs 8.6%, P = 0.49), and length of postoperative hospital stay (13 vs 14 days, P = 0.50). Lymph node harvest was significantly higher with MIE (35 vs 21, P < 0.001), a longer median survival was also evident compared to the open group (42.3 vs 24.7 months, P = 0.03). CONCLUSION: Although requiring longer operative time, MIE led to less wound and respiratory complications without jeopardizing surgical and oncological outcome. The more comprehensive lymphadenectomy could potentially improve prognosis. DISCLOSURE: All authors have declared no conflicts of interest.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Laparoscopia/métodos , Neoplasias de Células Escamosas/cirurgia , Complicações Pós-Operatórias/etiologia , Adulto , Bases de Dados Factuais , Esofagectomia/efeitos adversos , Feminino , Humanos , Laparoscopia/efeitos adversos , Laparotomia/efeitos adversos , Laparotomia/métodos , Excisão de Linfonodo/efeitos adversos , Excisão de Linfonodo/métodos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Complicações Pós-Operatórias/epidemiologia , Pontuação de Propensão , Estudos Prospectivos , Resultado do Tratamento
12.
Soft Matter ; 13(33): 5597-5603, 2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28730197

RESUMO

We present a detailed study on the ionic transport properties of polyethylene oxide (PEO) thin films prepared under different conditions. Using a state-of-the-art Atomic Force Microscopy (AFM) methodology, we simultaneously acquired the nanostructured topography of these semicrystalline polymer films as well as the corresponding dielectric function; in the latter case by probing the frequency-dependent tip-sample electrical interactions. By means of this AFM protocol, we studied the ionic conductivity in the PEO amorphous phase and its dependence on film preparation conditions. In general, for any preparation method, we found a distribution of conductivities ranging from 10-14 to 10-6 S cm-1. Specifically, PEO thin films crystallized from the melt presented relatively high conductivity values, which decreased in the PEO films prepared from solutions at room temperature depending on solvent polarity. We discuss our results by considering the molecular arrangement of the polymer segments in the complex amorphous phase, which is strongly influenced by the PEO crystallization route.

13.
Geophys Res Lett ; 44(9): 4304-4312, 2017 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-30166741

RESUMO

Climate models have consistently projected a drying trend in the southwestern United States, aiding speculation of increasing dust storms in this region. Long-term climatology is essential to documenting the dust trend and its response to climate variability. We have reconstructed long-term dust climatology in the western United States, based on a comprehensive dust identification method and continuous aerosol observations from the Interagency Monitoring of Protected Visual Environments (IMPROVE) network. We report here direct evidence of rapid intensification of dust storm activity over American deserts in the past decades (1988-2011), in contrast to reported decreasing trends in Asia and Africa. The frequency of windblown dust storms has increased 240% from 1990s to 2000s. This dust trend is associated with large-scale variations of sea surface temperature in the Pacific Ocean, with the strongest correlation with the Pacific Decadal Oscillation. We further investigate the relationship between dust and Valley fever, a fast-rising infectious disease caused by inhaling soil-dwelling fungus (Coccidioides immitis and C. posadasii) in the southwestern United States. The frequency of dust storms is found to be correlated with Valley fever incidences, with a coefficient (r) comparable to or stronger than that with other factors believed to control the disease in two endemic centers (Maricopa and Pima County, Arizona).

14.
Exp Cell Res ; 348(2): 146-154, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27658568

RESUMO

PURPOSE: This study aims to examine the expression profiles miR-1288 in oesophageal squamous cell carcinoma (ESCC). The cellular implications and target interactions of ESCC cells following miR-1288 overexpression was also examined. METHODS: In total, 120 oesophageal tissues (90 primary ESCCs and 30 non-neoplastic tissues) were recruited for miR-1288 expression analysis using qRT-PCR. An exogenous miR-1288 mimic and its inhibitor were used to explore the in-vitro effects of miR-1288 on ESCC cells by performing cell proliferation, colony formation, cell invasion and migration assays. Localisation and modulatory changes of various miR-1288 regulated proteins such as FOXO1, p53, TAB3, BCL2 and kRAS was examined using immunofluorescence and western blot. RESULTS: Overexpression of miR-1288 was more often noted in ESCC tissues when compared to non-neoplastic oesophageal tissues. High expression was often noted in high grade carcinomas and with metastases. Patients with high levels of miR-1288 expression showed a slightly better survival compared to patients with low miR-1288 levels. Furthermore, overexpression of miR-1288 showed increased cell proliferation and colony formation, improved cell migration and enhanced cell invasion properties in ESCC cells. In addition, miR-1288 overexpression in ESCC cells showed repression of cytoplasmic tumour suppressor FOXO1 protein expression. Inversely, inhibition of miR-1288 expression exhibited remarkable upregulation of FOXO1 protein, while expressions of other tested proteins remain unchanged. CONCLUSIONS: Up regulation of miR-1288 expression in ESCC tissues and miR-1288 induced oncogenic features of ESCC cells in-vitro indicates the oncogenic roles of miR-1288 in ESCCs. Overexpression of miR-1288 play a key role in the pathogenesis of ESCCs and its modulation may have potential therapeutic value in patients with ESCC.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Membrana Basal/metabolismo , Carcinoma de Células Escamosas/patologia , Extratos Celulares , Linhagem Celular Tumoral , Proliferação de Células , Células Clonais , Regulação para Baixo/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Feminino , Imunofluorescência , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Gradação de Tumores , Reprodutibilidade dos Testes , Análise de Sobrevida , Transfecção , Ensaio Tumoral de Célula-Tronco
15.
Dig Endosc ; 29 Suppl 2: 18-25, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28425657

RESUMO

Esophagogastric junction (EGJ) adenocarcinoma has been on the increase in Western countries. However, in Asian countries, data on the incidence of EGJ adenocarcinoma are evidently lacking. In the present review, we focus on the current clinical situation of EGJ adenocarcinoma in three Asian countries: Japan, Hong Kong, and Malaysia. The incidence of EGJ adenocarcinoma has been reported to be gradually increasing in Malaysia and Japan, whereas it has stabilized in Hong Kong. However, the number of cases in these countries is comparatively low compared with Western countries. A reason for the reported difference in the incidence and time trend of EGJ adenocarcinoma among the three countries may be explained by two distinct etiologies: one arising from chronic gastritis similar to distal gastric cancer, and the other related to gastroesophageal reflux disease similar to esophageal adenocarcinoma including Barrett's adenocarcinoma. This review also shows that there are several concerns in clinical practice for EGJ adenocarcinoma. In Hong Kong and Malaysia, many EGJ adenocarcinomas have been detected at a stage not amenable to endoscopic resection. In Japan, histological curability criteria for endoscopic resection cases have not been established. We suggest that an international collaborative study using the same definition of EGJ adenocarcinoma may be helpful not only for clarifying the characteristics of these cancers but also for improving the clinical outcome of these patients.


Assuntos
Adenocarcinoma/epidemiologia , Adenocarcinoma/terapia , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/terapia , Junção Esofagogástrica , Adenocarcinoma/diagnóstico , Neoplasias Esofágicas/diagnóstico , Hong Kong/epidemiologia , Humanos , Incidência , Japão/epidemiologia , Malásia/epidemiologia
16.
Dig Endosc ; 29 Suppl 2: 26-36, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28425653

RESUMO

BACKGROUND AND AIM: Western studies have suggested two distinct etiologies of esophagogastric junction (EGJ) cancer: Helicobacter pylori-associated atrophic gastritis and non-atrophic gastric mucosa resembling esophageal adenocarcinoma. The present study investigated whether endoscopic gastric mucosal atrophy can distinguish between these two types of EGJ adenocarcinoma. METHODS: Data were collected from patients with Siewert type II, T1 EGJ adenocarcinoma who underwent endoscopic or surgical resection at eight Japanese institutions in 2010-2015. Clinicopathological characteristics of EGJ cancers with and without endoscopic gastric mucosal atrophy were compared. EGJ was defined as the lower end of the palisade vein and/or the top of the gastric folds. RESULTS: Of the 229 patients identified, 161 had endoscopic gastric mucosal atrophy and 68 did not. The latter group was younger (64 vs 70 years, P = 0.000); had a higher proportion of patients negative for H. pylori (90% vs 47%, P < 0.0001); and had higher rates of gastroesophageal reflux disease symptoms (43% vs 12%, P = 0.017), mucosal breaks (25% vs 15%, P = 0.009), Barrett's esophagus (BE, 78% vs 42%, P < 0.0001), and tumors above the EGJ (81% vs 19%, P < 0.0001) and on the upper-right side (74% vs 38%, P < 0.0001) than the former group. Multivariate analysis showed that H. pylori positivity (odds ratio [OR] = 13.0, P < 0.001), long-segment BE (OR = 0.025, P = 0.033), and longitudinal (OR = 8.6, P = 0.001) and circumferential (OR = 4.7, P = 0.006) tumor locations were independently associated with gastric mucosal atrophy. CONCLUSION: Two distinct types of EGJ cancer were identified, with and without endoscopic gastric mucosal atrophy. These types were associated with different tumor locations.


Assuntos
Adenocarcinoma/patologia , Endoscopia Gastrointestinal , Neoplasias Esofágicas/patologia , Junção Esofagogástrica , Mucosa Gástrica/patologia , Gastrite/patologia , Adenocarcinoma/microbiologia , Idoso , Atrofia , Neoplasias Esofágicas/microbiologia , Feminino , Gastrite/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
J Environ Sci (China) ; 57: 15-23, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28647234

RESUMO

Mineral particles or particulate matters (PMs) emitted during agricultural activities are major recurring sources of atmospheric aerosol loading. However, precise PM inventory from agricultural tillage and harvest in agricultural regions is challenged by infrequent local emission factor (EF) measurements. To understand PM emissions from these practices in northeastern China, we measured EFs of PM10 and PM2.5 from three field operations (i.e., tilling, planting and harvesting) in major crop production (i.e., corn and soybean), using portable real-time PM analyzers and weather station data. County-level PM10 and PM2.5 emissions from agricultural tillage and harvest were estimated, based on local EFs, crop areas and crop calendars. The EFs averaged (107±27), (17±5) and 26mg/m2 for field tilling, planting and harvesting under relatively dry conditions (i.e., soil moisture <15%), respectively. The EFs of PM from field tillage and planting operations were negatively affected by topsoil moisture. The magnitude of PM10 and PM2.5 emissions from these three activities were estimated to be 35.1 and 9.8 kilotons/yr in northeastern China, respectively, of which Heilongjiang Province accounted for approximately 45%. Spatiotemporal distribution showed that most PM10 emission occurred in April, May and October and were concentrated in the central regions of the northeastern plain, which is dominated by dryland crops. Further work is needed to estimate the contribution of agricultural dust emissions to regional air quality in northeastern China.


Assuntos
Agricultura/métodos , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Agricultura/estatística & dados numéricos , China , Produtos Agrícolas , Estações do Ano
18.
J Environ Sci (China) ; 54: 101-113, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28391918

RESUMO

This study presents the mass concentrations of PM2.5, O3, SO2 and NOx at one urban, one suburban and two rural locations in the Changchun region from September 25 to October 27 2013. Major chemical components of PM2.5 at the four sites were daily sampled and analyzed. Most of daily concentrations of SO2 (7-82µg/m3), O3 (27-171µg/m3) and NOx (14-213µg/m3) were below the limits of the National Ambient Air Quality Standard (NAAQS) in China. However, PM2.5 concentrations (143-168µg/m3) were 2-fold higher than NAAQS. Higher PM2.5 concentrations (~150µg/m3) were measured during the pre-harvest and harvest at the urban site, while PM2.5 concentrations significantly increased from 250 to 400µgm-3 at suburban and rural sites with widespread biomass burning. At all sites, PM2.5 components were dominated by organic carbon (OC) and followed by soluble component sulfate (SO42-), ammonium (NH4+) and nitrate (NO3-). Compared with rural sites, urban site had a higher mineral contribution and lower potassium (K+ and K) contribution to PM2.5. Severe atmospheric haze events that occurred from October 21 to 23 were attributed to strong source emissions (e.g., biomass burning) and unfavorable air diffusion conditions. Furthermore, coal burning originating from winter heating supply beginning on October 18 increased the atmospheric pollutant emissions. For entire crop harvest period, the Positive Matrix Factorization (PMF) analysis indicated five important emission contributors in the Changchun region, as follows: secondary aerosol (39%), biomass burning (20%), supply heating (18%), soil/road dust (14%) and traffic (9%).


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Poeira/análise , Monitoramento Ambiental , Aerossóis/análise , Agricultura , China , Material Particulado/análise
19.
Gastroenterology ; 149(7): 1825-1836.e5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26302489

RESUMO

BACKGROUND & AIMS: The DnaJ (Hsp40) homolog, subfamily B, member 6 (DNAJB6) is part of a family of proteins that regulates chaperone activities. One of its isoforms, DNAJB6a, contains a nuclear localization signal and regulates ß-catenin signaling during breast cancer development. We investigated the role of DNAJB6 in the pathogenesis of esophageal squamous cell carcinoma (ESCC). METHODS: We performed immunohistochemical analyses of primary ESCC samples and lymph node metastases from a cohort of 160 patients who underwent esophagectomy with no preoperative chemoradiotherapy at Hong Kong Queen Mary Hospital. Data were collected on patient outcomes over a median time of 12.1 ± 2.9 months. Retrospective survival association analyses were performed. Wild-type and mutant forms of DNAJB6a were overexpressed in cancer cell lines (KYSE510, KYSE 30TSI, KYSE140, and KYSE70TS), which were analyzed in proliferation and immunoblot assays, or injected subcutaneously into nude mice. Levels of DNAJB6 were knocked down in ESCC cell lines (KYSE450 and T.Tn), immortalized normal esophageal epithelial cell lines (NE3 and NE083), and other cells with short hairpin RNAs, or by genome engineering. Bimolecular fluorescence complementation was used to study interactions between proteins in living cells. RESULTS: In primary ESCC samples, patients whose tumors had high nuclear levels of DNAJB6 had longer overall survival times (19.2 ± 1.8 months; 95% confidence interval [CI], 15.6-22.8 mo) than patients whose tumors had low nuclear levels of DNAJB6 (12.6 ± 1.4 mo; 95% CI, 9.8-15.4 mo; P = .004, log-rank test). Based on Cox regression analysis, patients whose tumors had high nuclear levels of DNAJB6 had a lower risk of death than patients with low levels (hazard ratio, 0.562; 95% CI, 0.379-0.834; P = .004). Based on log-rank analysis and Cox regression analysis, the combination of the nuclear level of DNAJB6 and the presence of lymph node metastases at diagnosis could be used to stratify patients into groups with good or bad outcomes (P < .0005 for both analyses). There was a negative association between the nuclear level of DNAJB6 and the presence of lymph node metastases (P = .022; Pearson χ(2) test). Cancer cell lines that overexpressed DNAJB6a formed tumors more slowly in nude mice than control cells or cells that expressed a mutant form of DNAJB6a that did not localize to the nucleus. DNAJB6 knockdown in cancer cell lines promoted their growth as xenograft tumors in mice. A motif of histidine, proline, and aspartic acid in the J domain of DNAJB6a was required for its tumor-suppressive effects and signaling via AKT1. Loss of DNAJB6a resulted in up-regulation of AKT signaling in cancer cell lines and immortalized esophageal epithelial cells. Expression of a constitutively active form of AKT1 restored proliferation to tumor cells that overexpressed DNAJB6a, and DNAJB6a formed a complex with AKT1 in living cells. The expression of DNAJB6a reduced the sensitivity of ESCC to AKT inhibitors; the expression level of DNAJB6a affected AKT signaling in multiple cancer cell lines. CONCLUSIONS: Nuclear localization of DNAJB6 is associated with longer survival times of patients with ESCC. DNAJB6a reduces AKT signaling, and DNAJB6 expression in cancer cells reduces their proliferation and growth of xenograft tumors in mice. DNAJB6a might be developed as a biomarker for progression of ESCC.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Núcleo Celular/metabolismo , Proliferação de Células , Neoplasias Esofágicas/enzimologia , Proteínas de Choque Térmico HSP40/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transporte Ativo do Núcleo Celular , Idoso , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago , Esofagectomia , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico HSP40/genética , Xenoenxertos , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Chaperonas Moleculares/genética , Mutação , Proteínas do Tecido Nervoso/genética , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , Estudos Retrospectivos , Fatores de Risco , Transdução de Sinais , Fatores de Tempo , Transfecção , Resultado do Tratamento
20.
Tumour Biol ; 37(2): 2127-36, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26346170

RESUMO

Esophageal squamous cell carcinoma (ESCC) is the predominant type of esophageal cancer in Asia. Cisplatin is commonly used in chemoradiation for unresectable ESCC patients. However, the treatment efficacy is diminished in patients with established cisplatin resistance. To understand the mechanism leading to the development of cisplatin resistance in ESCC, we compared the proteomes from a cisplatin-resistant HKESC-2R cell line with its parental-sensitive counterpart HKESC-2 to identify key molecule involved in this process. Mass spectrometry analysis detected 14-3-3σ as the most abundant molecule expressed exclusively in HKESC-2R cells, while western blot result further validated it to be highly expressed in HKESC-2R cells when compared to HKESC-2 cells. Ectopic expression of 14-3-3σ increased cisplatin resistance in HKESC-2 cells, while its suppression sensitized SLMT-1 cells to cisplatin. Among the molecules involved in drug detoxification, drug transportation, and DNA repair, the examined DNA repair molecules HMGB1 and XPA were found to be highly expressed in HKESC-2R cells with high 14-3-3σ expression. Subsequent manipulation of 14-3-3σ by both overexpression and knockdown approaches concurrently altered the expression of HMGB1 and XPA. 14-3-3σ, HMGB1, and XPA were preferentially expressed in cisplatin-resistant SLMT-1 cells when compared to those more sensitive to cisplatin. In ESCC patients with poor response to cisplatin-based chemoradiation, their pre-treatment tumors expressed higher expression of HMGB1 than those with response to such treatment. In summary, our results demonstrate that 14-3-3σ induces cisplatin resistance in ESCC cells and that 14-3-3σ-mediated cisplatin resistance involves DNA repair molecules HMGB1 and XPA. Results from this study provide evidences for further work in researching the potential use of 14-3-3σ and DNA repair molecules HMGB1 and XPA as biomarkers and therapeutic targets for ESCC.


Assuntos
Proteínas 14-3-3/metabolismo , Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Neoplasias Esofágicas/metabolismo , Exorribonucleases/metabolismo , Western Blotting , Cromatografia Líquida de Alta Pressão , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/fisiologia , Carcinoma de Células Escamosas do Esôfago , Técnicas de Silenciamento de Genes , Proteína HMGB1/metabolismo , Humanos , Espectrometria de Massas , Reação em Cadeia da Polimerase , Transcriptoma , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo
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