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1.
Sci Total Environ ; 946: 173936, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885703

RESUMO

The leaf economics spectrum (LES) describes the covariation of traits relevant for carbon and nutrient economy in different plant species. However, much less is known about the correlation of LES with leaf water economy, not only because some woody species do not follow the rules, but also because they are rarely tested on the widespread, non-native, fast-growing trees. We hypothesized that fast-growing exotic species that spread on the fast side of the LES coordinate their water-use strategies (WUS) to maintain rapid growth, and that the pattern of coordination differs between evergreen and deciduous forests. Using 4 exotic and 4 native species from evergreen and deciduous broadleaf forests in China, we measured 17 traits of LES and WUS and analyzed their functional roles in different species groups. Our results suggest that LES plays a more important role in the coexistence of species within a community, while WUS contributes more to the distribution of species across different regions. The multidimensional coordination of LES and WUS could better explain the growth and distribution of different plant species and shed light on the coexistence of species from different forest types, especially fast-growing woody exotics.

2.
Environ Sci Pollut Res Int ; 31(6): 9811-9830, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38198083

RESUMO

The number of cars is increasing every year and the environmental aspects of transport are becoming a hot topic. The spatial and temporal patterns of motor vehicle carbon monoxide (CO) emissions are still unclear due to the unbalanced economic development and heterogeneous geographic conditions of China. With the objective of realizing a reduction in motor vehicle CO emissions, his study explores the transport carbon emission reduction pathways of China from motor vehicle CO emission. Firstly, the entropy method is adopted to comprehensively evaluate the CO emissions from motor vehicles in each province; secondly, the development of a Geographically and Temporally Weighted Regression (GTWR) model facilitates the examination of the spatiotemporal dynamics pertaining to the influencing factors of motor vehicle CO emissions within each province.; finally, the characteristics of motor vehicle CO emissions in ETS pilot areas and non-ETS pilot areas are compared. The results show that: (1) After the completion of the six ETS pilot areas in 2011, the CO emission from motor vehicles is reduced by 18% compared with 2010.(2)The entropy method shows that the largest CO emissions from motor vehicles are from Beijing, Shanghai, Guangdong and other provinces with high economic levels.(3) The results of the GTWR model show that the positive effects of economic level, population size, road mileage intensity and motor vehicle intensity on motor vehicle CO emissions are decreasing year by year. The negative effect of metro line intensity on CO emission decreases year by year. This study can help decision makers to identify the high emission areas, understand the influencing factors, and formulate emission reduction measures to achieve the purpose of carbon emission reduction in transport.


Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Emissões de Veículos/análise , Monóxido de Carbono/análise , Poluentes Atmosféricos/análise , China , Veículos Automotores
3.
Sci Rep ; 13(1): 19291, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935754

RESUMO

Acute appendicitis is one of the common acute abdominal diseases in pediatrics. However, the implementation of radiological examination guided endoscopic retrograde appendicitis therapy (ERAT) in adults is limited in children. Our previous research explored the non-invasive guidance of high-frequency ultrasound (HFUS) for ERAT and achieved good therapeutic effects. This study mainly focuses on exploring the application value of HFUS in the feasibility assessment of ERAT in children with appendicitis. 163 children with appendicitis received ERAT guided by HFUS were analyzed retrospectively. According to the parameters evaluated by HFUS before and during ERAT, the results indicated that the distance between the appendix orifice and the ileocecal valve significantly affected the time required for the guidewire to enter the appendix cavity (P < 0.05). The diameter and the texture of the fecalith, the thickness of the intestinal wall of the appendiceal orifice all had significant effects on the successful removal of the fecalith (P < 0.05). The success rate, treatment time and final flushing effect of the guidewire to reach the blind end of the appendix were significantly affected by the tortuosity of the appendix and whether there was adhesion with surrounding tissues (P < 0.05). HFUS can accurately assess the feasibility of ERAT in children with appendicitis.


Assuntos
Apendicite , Apêndice , Impacção Fecal , Adulto , Humanos , Criança , Apendicite/diagnóstico por imagem , Apendicite/cirurgia , Estudos Retrospectivos , Estudos de Viabilidade , Apêndice/diagnóstico por imagem , Apêndice/cirurgia , Doença Aguda
4.
Environ Geochem Health ; 45(7): 5467-5480, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37099043

RESUMO

Antimony (Sb) and arsenic (As) co-contamination occurs in Sb smelting areas and is harmful to the surrounding ecological environment. The purpose of this study is to explore the spatial distribution characteristics of Sb and As in abandoned Sb smelting area and carry out risk assessments. Soil samples were collected from the smelting area profile and background points, and groundwater samples were also collected. Samples from two geological background sections were collected to understand the geological background characteristics of Sb and As. The spatial distribution was drawn via the inverse distance weighted interpolation method. The hazard assessment was carried out by the geo-accumulation index and potential ecological hazard methods. The results showed that special high geological background value of Sb and As in study area. Sb and As co-contamination is one of the characters in soil. And the contents of Sb and As decrease as depth increases, reflecting the weak migration capacity. The spatial distribution of Sb and As is affected by slag distribution and rainfall leaching. The Sb content in groundwater was higher in the wet and normal seasons than in the dry season, slag leaching may be one of the elements. The potential ecological hazards of Sb and As are high and considerable, respectively. In abandoned smelting area with high geological background values, it is necessary to focus on the pollution abatement and protection of ecological health.


Assuntos
Arsênio , Poluentes do Solo , Antimônio/análise , Arsênio/análise , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Solo , China , Medição de Risco
5.
Medicine (Baltimore) ; 101(43): e31341, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36316866

RESUMO

The aim was to illuminate the difference in incidence, mortality, and disability-adjusted life-years (DALYs) of gastric cancer (GC) between the United States of America (US) and China. The multiple management was analyzed with stratification to explore an effective survival improvement strategy. The Global Burden of Disease Study data was analyzed to assess GC morbidity, mortality and DALYs from 1990 to 2019 in the US and China. The age-period-cohort model was established to generate estimation of metrics. Verification was completed and stratified analysis of the multiple management was performed by accessing data of Surveillance, Epidemiology, and End Results database in 1992 to 2019. Continuous downtrends in GC incidence, mortality and DALYs from 1990 to 2019 and persistent uptrends in 1-, 3-year survival from 1992 to 2019 were observed in the US population. In the Chinese population, the overall trends of incidence, mortality and DALYs decreased with a fluctuating manner. The lower overall survival rates were observed in elderly, unmarried patients, distant disease and poor grade, as well as patients lacking of medical treatment (P < .05). In stratified analyses, single local therapy decreased and the other modalities increased over time across different stages. Moreover, combined treatment and single systemic therapy decreased, but single local and conservative therapy increased with age. The study quantified the incidence, GC-specific mortality and DALYs in the US and China and estimated stage profiles, 1- and 3-year survival in the US. The heavy burden on later-onset GC (>70) and potential increase on early-onset GC (<40) needed to be addressed. Combined modalities and single chemotherapy were becoming more widely used over time, however, their uses decreased with age because of poor physical fitness. Our findings provide new insights into management tailoring appropriately to specific subgroups contributes to the increasing survival rate.


Assuntos
Neoplasias Gástricas , Humanos , Idoso , Incidência , Anos de Vida Ajustados por Qualidade de Vida , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/terapia , Morbidade , Doença Crônica
6.
Int J Nanomedicine ; 17: 4933-4946, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275481

RESUMO

Background: The early detection of atherosclerotic lesions is particularly important for risk prediction of acute cardiovascular events. Macrophages apoptosis was significantly associated with the degree of AS lesions and especially contributed to plaque vulnerability. In this research, we mainly sought to explore the feasibility of a home-made AV-nanobubbles (NBAV) for visualization of apoptotic macrophages and assessment of atherosclerosis (AS) lesions by contrast-enhanced ultrasound (CEUS) imaging. Methods: NBAV were prepared by "Optimized Thin-Film Hydration" and "Biotin-Avidin-Biotin" methods. Then, the characterization and echogenicity of NBAV were measured and analyzed in vitro. The targeting ability of NBAV to ox-LDL-induced apoptotic macrophages was observed by laser scanning confocal microscope. The ApoE-/- mice mode fed with high fat diet were observed by high-frequency ultrasound, microanatomy and oil red O staining. CEUS imaging in vivo was performed on AS plaques with NBAV and NBCtrl injection through the tail vein in turn in ApoE-/- mice. After CEUS imaging, the plaques were confirmed and analyzed by histopathological and immunological assessment. Results: The prepared NBAV had a nano-scale size distribution with a low PDI and a negative zeta potential. Moreover, NBAV showed an excellent stability and exhibited a significantly echogenic signal than saline in vitro. In addition, we found that NBAV could target apoptotic macrophages induced by ox-LDL. Compared with NBCtrl, CEUS imaging of NBAV showed strong and sustained echo enhancement in plaque area of aortic arch in vivo. Further research showed that NBAV sensitive plaques presented more significant pathological changes with several vulnerable plaque features and abundant TUNEL-positive area. Conclusion: NBAV displayed a sensitive indicator to evaluate apoptotic macrophages, indicating a promising CEUS molecular probe for AS lesions and vulnerable plaques identification.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Camundongos , Avidina , Biotina , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Aterosclerose/diagnóstico por imagem , Aterosclerose/patologia , Apolipoproteínas E/genética , Macrófagos/patologia , Sondas Moleculares
7.
J Cachexia Sarcopenia Muscle ; 13(1): 343-354, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34862759

RESUMO

BACKGROUND: Completing Patient-Generated Subjective Global Assessment (PG-SGA) questionnaires is time consuming. This study aimed to develop and validate an easy-to-use modified PG-SGA (mPG-SGA) for cancer patients. METHODS: Seventy professionals assessed the content validity, comprehensibility, and difficulty of the full PG-SGA. A survey including the PG-SGA and other questionnaires was completed by 34 071 adult hospitalized cancer patients with first cancer diagnosis or recurrent disease with any tumour comorbidities from the INSCOC study. Among them, 1558 patients were followed for 5 years after admission. Reliability and rank correlation were estimated to assess the consistency between PG-SGA items and to select mPG-SGA items. The external and internal validity, test-retest reliability, and predictive validity were tested for the mPG-SGA via comparison with both the PG-SGA and abridged PG-SGA (abPG-SGA). RESULTS: After deleting items that more than 50% of professionals considered difficult to evaluate (Worksheet 4) and items with an item-total correlation <0.1, the mPG-SGA was constructed. Nutritional status was categorized using mPG-SGA scores as well-nourished (0 points) or mildly (1-2 points), moderately (3-6 points), or severely malnourished (≥7 points) based on the area under curve (0.962, 0.989, and 0.985) and maximal sensitivity (0.924, 0.918, and 0.945) and specificity (1.000, 1.000, and 0.938) of the cut-off scores. The external and internal validity and test-retest reliability were good. Significant median overall survival differences were found among nutritional status groups categorized by the mPG-SGA: 24, 18, 14, and 10 months for well-nourished, mildly malnourished, moderately malnourished, and severely malnourished, respectively (all Ps < 0.05). Neither the PG-SGA nor the abridged PG-SGA could discriminate the median overall survival differences between the well-nourished and mildly malnourished groups. CONCLUSIONS: We systematically developed and validated the mPG-SGA as an easier-to-use nutritional assessment tool for cancer patients. The mPG-SGA appears to have better predictive validity for survival than the PG-SGA and abridged PG-SGA.


Assuntos
Desnutrição , Neoplasias , Adulto , Humanos , Desnutrição/diagnóstico , Desnutrição/etiologia , Neoplasias/complicações , Neoplasias/diagnóstico , Avaliação Nutricional , Estado Nutricional , Reprodutibilidade dos Testes
8.
Chemosphere ; 279: 130558, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33887596

RESUMO

Soil pollution, caused by heavy metals, is an environmental problem that requires an urgent solution in China. Chemical passivation is a technology that uses various passivators to reduce the availability of heavy metals in soil and realize the remediation of contaminated soil. In this study, we examined the effects of fly ash (FA), alkali-fused fly ash (AFFA), swine manure biochar (SB), and modifying biochar (MB) on the leachability of Cu, Zn, Pb, and Cd via soil culture experiments. The results showed that the addition of AFFA, SB, and MB significantly reduced the extractable contents of Cu, Pb, and Cd in the soil. AFFA and MB had the best passivation effect, followed by SB and FA. The passivation effect on Pb was the best, followed by that on Cu and Cd. AFFA modification significantly improved the passivation effect of MB on Cu, Pb, and Cd in composite contaminated soil. With the addition of 3% MB, the Pb, Cu, and Cd extracted by TCLP decreased by 95.7, 74.1, and 59.1%, respectively. Correlation analysis, Fourier transform infrared spectrometry, scanning electron microscopy, and energy-dispersive X-ray spectroscopy showed that the passivation mechanism is mainly due to an increase in the soil pH, silicate content, and cohesiveness. The soil culture experiments in this study proved that MB is a low-cost and highly efficient organic-inorganic composite passivator for multi-metal contaminated soils.


Assuntos
Metais Pesados , Poluentes do Solo , Álcalis , Animais , China , Cinza de Carvão , Esterco , Metais Pesados/análise , Solo , Poluentes do Solo/análise , Suínos
9.
Int J Mol Sci ; 20(12)2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208067

RESUMO

Epigenetic modifications on individual bases in DNA and RNA can encode inheritable genetic information beyond the canonical bases. Among the nucleic acid modifications, DNA N6-methadenine (6mA) and RNA N6-methyladenosine (m6A) have recently been well-studied due to the technological development of detection strategies and the functional identification of modification enzymes. The current findings demonstrate a wide spectrum of 6mA and m6A distributions from prokaryotes to eukaryotes and critical roles in multiple cellular processes. It is interesting that the processes of modification in which the methyl group is added to adenine and adenosine are the same, but the outcomes of these modifications in terms of their physiological impacts in organisms are quite different. In this review, we summarize the latest progress in the study of enzymes involved in the 6mA and m6A methylation machinery, including methyltransferases and demethylases, and their functions in various biological pathways. In particular, we focus on the mechanisms by which 6mA and m6A regulate the expression of target genes, and we highlight the future challenges in epigenetic regulation.


Assuntos
Adenosina/análogos & derivados , Metilação de DNA , Epigênese Genética , Animais , Humanos , Metiltransferases/metabolismo , RNA/metabolismo
10.
Clin Pharmacol Ther ; 105(6): 1378-1385, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30771252

RESUMO

Despite recent advances in recognizing and reducing the risk of drug-drug interactions (DDIs) in developed countries, there are still significant challenges in managing DDIs in low-income countries (LICs) worldwide. In the treatment of major infectious diseases in these regions, multiple factors contribute to ineffective management of DDIs that lead to loss of efficacy or increased risk of adverse events to patients. Some of these difficulties, however, can be overcome. This review aims to evaluate the inherent complexities of DDI management in LICs from pharmacological standpoints and illustrate the unique barriers to effective management of DDIs, such as the challenges of co-infection and treatment settings. A better understanding of comprehensive drug-related properties, population-specific attributes, such as physiological changes associated with infectious diseases, and the use of modeling and simulation techniques are discussed, as they can facilitate the implementation of optimal treatments for infectious diseases at the individual patient level.


Assuntos
Anti-Infecciosos/uso terapêutico , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/economia , Interações Medicamentosas/fisiologia , Pobreza/economia , Anti-Infecciosos/economia , Anti-Infecciosos/metabolismo , Antituberculosos/economia , Antituberculosos/metabolismo , Antituberculosos/uso terapêutico , Doenças Transmissíveis/metabolismo , Humanos , Pobreza/tendências , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Tuberculose/economia , Tuberculose/metabolismo
12.
Environ Sci Pollut Res Int ; 25(28): 28431-28444, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30088244

RESUMO

Assessing the uptake of trace gases by forests contributes to understanding the mechanisms of gas exchange between vegetation and the atmosphere and to evaluating the potential risk of these pollutant gases to forests. In this study, the multi-timescale characteristics of the stomatal uptake of NO, NO2, SO2 and O3 by Schima superba, Eucalyptus citriodora and Acacia auriculiformis were investigated by continuous sap flow measurements for a 3-year period. The peak canopy stomatal conductance (GC) for these three species appeared between 9:00 and 12:00, which was jointly regulated by the vapour pressure deficit (VPD) and photosynthetically active radiation (PAR). Additionally, annual and seasonal variations in the stomatal uptake of trace gases for these three tree species suggested that there was a combination effect between canopy stomatal conductance and ambient concentration on the uptake of trace gases. Furthermore, the result demonstrated that the trace gas absorption capacities among these three forest types followed the order of S. superba > E. citriodora > A. auriculiformis. The findings of this study have theoretical significance and application value in assessing air purification and the risk of harm to forests in Southern China.


Assuntos
Poluentes Atmosféricos/química , Florestas , Óxidos de Nitrogênio/análise , Ozônio/análise , Dióxido de Enxofre/análise , Árvores/metabolismo , China , Fotossíntese , Transpiração Vegetal , Estações do Ano , Clima Tropical
13.
J Control Release ; 276: 113-124, 2018 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-29522835

RESUMO

In vivo assessment of apoptotic response to cancer therapy is believed to be very important for optimizing management of treatment. However, few noninvasive strategies are currently available to monitor the therapeutic response in vivo. Ultrasonography has been used to detect apoptotic cell death in vivo, but a high-frequency transducer is needed. Fortunately, the capability of ultrasound contrast agents (UCAs) to exit the leaky vasculature of tumors enables ultrasound-targeted imaging of molecular events in response to cancer therapy. In this study, we prepared a novel nano-sized UCA, namely, Annexin V-conjugated nanobubbles (AV-NBs, 635.5 ±â€¯25.4 nm). In vitro studies revealed that AV-NBs were relatively stable and highly echogenic. Moreover, these AV-NBs could easily extravasate into the tumor vasculature and recognize the apoptotic cells with high specificity and affinity in tumors sensitive to chemotherapy. Ultrasound imaging results demonstrated that AV-NBs had higher echogenicity and significantly greater enhancement compared with the untargeted control NBs (P < 0.01) inside the tumors after chemotherapy. Taken together, this study provides a promising method to accurately evaluate therapeutic effects at the molecular level to support cancer management.


Assuntos
Anexina A5/administração & dosagem , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Cisplatino/administração & dosagem , Meios de Contraste/administração & dosagem , Nanoestruturas/administração & dosagem , Neoplasias/diagnóstico por imagem , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/tratamento farmacológico , Ultrassonografia
14.
Ecotoxicol Environ Saf ; 153: 68-77, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29407740

RESUMO

Laboratory analysis of trace metals using inductively coupled plasma (ICP) spectroscopy is not cost effective, and the complex spatial distribution of soil trace metals makes their spatial analysis and prediction problematic. Thus, for the health risk assessment of exposure to trace metals in soils, portable X-ray fluorescence (PXRF) spectroscopy was used to replace ICP spectroscopy for metal analysis, and robust geostatistical methods were used to identify spatial outliers in trace metal concentrations and to map trace metal distributions. A case study was carried out around an industrial area in Nanjing, China. The results showed that PXRF spectroscopy provided results for trace metal (Cu, Ni, Pb and Zn) levels comparable to ICP spectroscopy. The results of the health risk assessment showed that Ni posed a higher non-carcinogenic risk than Cu, Pb and Zn, indicating a higher priority of concern than the other elements. Sampling locations associated with adverse health effects were identified as 'hotspots', and high-risk areas were delineated from risk maps. These 'hotspots' and high-risk areas were in close proximity to and downwind from petrochemical plants, indicating the dominant role of industrial activities as the major sources of trace metals in soils. The approach used in this study could be adopted as a cost-effective methodology for screening 'hotspots' and priority areas of concern for cost-efficient health risk management.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Oligoelementos/análise , China , Análise Custo-Benefício , Monitoramento Ambiental/estatística & dados numéricos , Humanos , Indústrias , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Análise Espacial , Espectrometria por Raios X
15.
Clin Pharmacol Ther ; 103(5): 854-867, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28990182

RESUMO

Our recent studies have shown that chronic kidney disease (CKD) affects the pharmacokinetics (PKs) of cytochrome P450 (CYP)2D6-metabolized drugs, whereas effects were less evident on CYP3A4/5. Therefore, the effect of CKD on the disposition of CYP1A2-metabolized, CYP2C8-metabolized, CYP2C9-metabolized, CYP2C19-metabolized, and organic anion-transporting polypeptide (OATP)-transported drugs was investigated. We identified dedicated CKD studies with 6, 5, 6, 4, and 12 "model" substrates for CYP1A2, CYP2C8, CYP2C9, CYP2C19, and OATP, respectively. Our analyses suggest that clearance of OATP substrates decreases as kidney function declines. Similar trends were seen for CYP2C8; but overlap between some CYP2C8 and OATP substrates highlights that their interplay needs further investigation. In contrast, the effect of CKD on CYP1A2, CYP2C9, and CYP2C19 was variable and modest compared to CYP2C8 and OATP. This improved understanding of elimination-pathway-dependency in CKD is important to inform the need and conduct of PK studies in these patients for nonrenally eliminated drugs.


Assuntos
Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C8/genética , Citocromo P-450 CYP2C9/genética , Transportadores de Ânions Orgânicos/genética , Insuficiência Renal Crônica/genética , Inibidores das Enzimas do Citocromo P-450/farmacologia , Humanos , Insuficiência Renal Crônica/tratamento farmacológico
16.
J Clin Pharmacol ; 57(1): 105-109, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27365151

RESUMO

This report summarizes the discussions and recommendations of the workshop titled "Specific Population Drug Dosing Recommendations: Shifting from Clinical Studies to Predict and Confirm," which preceded the 2015 American Association of Pharmaceutical Scientists annual meeting. Participants from the pharmaceutical industry, regulatory agencies (FDA and EMA), and academia discussed the current state, challenges, opportunities, and future direction of utilizing model-based approaches to inform dosing recommendations in specific populations.


Assuntos
Pesquisa Biomédica/métodos , Indústria Farmacêutica/métodos , Educação/métodos , Modelos Biológicos , Preparações Farmacêuticas/administração & dosagem , Relatório de Pesquisa , Pesquisa Biomédica/tendências , Indústria Farmacêutica/tendências , Educação/tendências , Florida , Humanos , Preparações Farmacêuticas/metabolismo , Relatório de Pesquisa/tendências
17.
Magn Reson Imaging ; 37: 195-202, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27919785

RESUMO

BACKGROUND: Diffusion-weighted MRI (DWI) signal attenuation is often not mono-exponential (i.e. non-Gaussian diffusion) with stronger diffusion weighting. Several non-Gaussian diffusion models have been developed and may provide new information or higher sensitivity compared with the conventional apparent diffusion coefficient (ADC) method. However the relative merits of these models to detect tumor therapeutic response is not fully clear. METHODS: Conventional ADC, and three widely-used non-Gaussian models, (bi-exponential, stretched exponential, and statistical model), were implemented and compared for assessing SW620 human colon cancer xenografts responding to barasertib, an agent known to induce apoptosis via polyploidy. Bayesian Information Criterion (BIC) was used for model selection among all three non-Gaussian models. RESULTS: All of tumor volume, histology, conventional ADC, and three non-Gaussian DWI models could show significant differences between control and treatment groups after four days of treatment. However, only the non-Gaussian models detected significant changes after two days of treatment. For any treatment or control group, over 65.7% of tumor voxels indicate the bi-exponential model is strongly or very strongly preferred. CONCLUSION: Non-Gaussian DWI model-derived biomarkers are capable of detecting tumor earlier chemotherapeutic response of tumors compared with conventional ADC and tumor volume. The bi-exponential model provides better fitting compared with statistical and stretched exponential models for the tumor and treatment models used in the current work.


Assuntos
Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Imagem de Difusão por Ressonância Magnética/métodos , Dimetil Sulfóxido/administração & dosagem , Organofosfatos/uso terapêutico , Quinazolinas/uso terapêutico , Animais , Teorema de Bayes , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Nus , Modelos Estatísticos , Inibidores de Proteínas Quinases/uso terapêutico
18.
Artigo em Inglês | MEDLINE | ID: mdl-27595294

RESUMO

In order to address the issue of excessive intake of aluminium (Al) from Al-containing food additives in the Chinese diet, this study conducted a dietary exposure assessment of Al in the general population based on the national surveillance data of Al content in foods and national food consumption data. It was found that the mean dietary exposure of the whole Chinese population to Al from Al-containing food additives was 1.795 mg kg‒1 bw week‒1, not exceeding the PTWI, while high dietary exposures (e.g., 97.5th percentile) to Al were 7.660 and 2.103-2.903 mg kg‒1 bw week‒1 for children, respectively, both exceeding the PTWI. It was found that the dietary exposure to Al for 32.5% of the total Chinese population and 42.6% of children aged 4-6 years exceeded the PTWI. Wheat flour and wheat-based products are the main source of dietary A l exposure (85% of the total intake); and puffed foods are the major source of Al intake for children. These findings suggested that consumption of Al-containing food additives could be a health concern for consumers with high food consumption (97.5th percentile) and children under the age of 14 years.


Assuntos
Alumínio/administração & dosagem , Alumínio/análise , Dieta , Exposição Ambiental/análise , Aditivos Alimentares/química , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alumínio/efeitos adversos , Criança , Pré-Escolar , China , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Triticum , Adulto Jovem
19.
Mol Pharm ; 13(9): 3130-40, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27467266

RESUMO

One of the characteristics of chronic kidney disease (CKD) is the accumulation of uremic solutes in the plasma. Less is known about the effects of uremic solutes on transporters that may play critical roles in pharmacokinetics. We evaluated the effect of 72 uremic solutes on organic anion transporter 1 and 3 (OAT1 and OAT3) using a fluorescent probe substrate, 6-carboxyfluorescein. A total of 12 and 13 solutes were identified as inhibitors of OAT1 and OAT3, respectively. Several of them inhibited OAT1 or OAT3 at clinically relevant concentrations and reduced the transport of other OAT1/3 substrates in vitro. Review of clinical studies showed that the active secretion of most drugs that are known substrates of OAT1/3 deteriorated faster than the renal filtration in CKD. Collectively, these data suggest that through inhibition of OAT1 and OAT3, uremic solutes contribute to the decline in renal drug clearance in patients with CKD.


Assuntos
Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Insuficiência Renal Crônica/metabolismo , Animais , Fluoresceínas/metabolismo , Humanos , Modelos Biológicos , Proteína 1 Transportadora de Ânions Orgânicos/análise , Transportadores de Ânions Orgânicos Sódio-Independentes/análise
20.
Int J Environ Res Public Health ; 12(8): 9799-808, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26295250

RESUMO

OBJECTIVES: In 2005, China acceded to the World Health Organization Framework Convention on Tobacco Control (WHO FCTC), the foundation for the global fight against tobacco. Certain cities in China have established local regulations to control tobacco use ahead of national policy; however, without the enforcement of statutory law, some of these regulations are merely lip service. The aim of the study was to assess the effects of city policy on smoking prevalence and on second-hand smoke (SHS) exposure status among non-smokers in Changchun City. METHODS: A cross-sectional survey covering a multiple-stage, representative sample of the urban population aged ≥15 years was conducted between 1 Dec 2013 and 31 Jan 2014. The WHO and the US Centers for Disease Control and Prevention developed the questionnaires used, which included demographic characteristics, smoking behaviors and SHS exposure status. RESULTS: Overall cigarette smoking prevalence was 23.5%; daily cigarette smoking prevalence was 21.2%. Smoking prevalence and cigarettes consumed per day was higher among men (p < 0.05) and those aged 45-64 years (p < 0.05). Among current smokers, 8.1% planned to quit within 12 months; 53.4% had no intention of quitting. Overall SHS exposure prevalence was 41.9% (workplace) and 34.1% (at home) over the previous 30 days. The weighted workplace SHS exposure prevalence increased with age. CONCLUSIONS: The high proportion of smokers with no intention of quitting and the high level of SHS exposure may constitute one of the most significant barriers to successful smoking cessation in the city. A continued drive to promote full implementation of the WHO FCTC is still needed.


Assuntos
Exposição Ambiental , Fumar/epidemiologia , Poluição por Fumaça de Tabaco/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , China/epidemiologia , Estudos Transversais , Monitoramento Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores Socioeconômicos , População Urbana , Adulto Jovem
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