Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
1.
Genomics ; 116(4): 110876, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38849019

RESUMO

Timely accurate and cost-efficient detection of colorectal cancer (CRC) is of great clinical importance. This study aims to establish prediction models for detecting CRC using plasma cell-free DNA (cfDNA) fragmentomic features. Whole-genome sequencing (WGS) was performed on cfDNA from 620 participants, including healthy individuals, patients with benign colorectal diseases and CRC patients. Using WGS data, three machine learning methods were compared to build prediction models for the stratification of CRC patients. The optimal model to discriminate CRC patients of all stages from healthy individuals achieved a sensitivity of 92.31% and a specificity of 91.14%, while the model to separate early-stage CRC patients (stage 0-II) from healthy individuals achieved a sensitivity of 88.8% and a specificity of 96.2%. Additionally, the cfDNA fragmentation profiles reflected disease-specific genomic alterations in CRC. Overall, this study suggests that cfDNA fragmentation profiles may potentially become a noninvasive approach for the detection and stratification of CRC.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/sangue , Neoplasias Colorretais/diagnóstico , Masculino , Pessoa de Meia-Idade , Feminino , Detecção Precoce de Câncer/métodos , Idoso , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/sangue , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Aprendizado de Máquina , Adulto , Sequenciamento Completo do Genoma/métodos , Fragmentação do DNA
2.
Pharm Res ; 40(6): 1447-1457, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36471026

RESUMO

Quantification of subvisible particles, which are generally defined as those ranging in size from 2 to 100 µm, is important as critical characteristics for biopharmaceutical formulation development. Micro Flow Imaging (MFI) provides quantifiable morphological parameters to study both the size and type of subvisible particles, including proteinaceous particles as well as non-proteinaceous features incl. silicone oil droplets, air bubble droplets, etc., thus enabling quantitative and categorical particle attribute reporting for quality control. However, limitations in routine MFI image analysis can hinder accurate subvisible particle classification. In this work, we custom-built a subvisible particle-aware Convolutional Neural Network, SVNet, which has a very small computational footprint, and achieves comparable performance to prior state-of-art image classification models. SVNet significantly improves upon current standard operating procedures for subvisible particulate assessments as confirmed by thorough real-world validation studies.


Assuntos
Produtos Biológicos , Tamanho da Partícula , Proteínas , Diagnóstico por Imagem , Redes Neurais de Computação
3.
Drug Metab Dispos ; 50(7): 909-922, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35489778

RESUMO

The multidrug resistance protein 1 (MDR1) P-glycoprotein (P-gp) is a clinically important transporter. In vitro P-gp inhibition assays have been routinely conducted to predict the potential for clinical drug-drug interactions (DDIs) mediated by P-gp. However, high interlaboratory and intersystem variability of P-gp IC50 data limits accurate prediction of DDIs using static models and decision criteria recommended by regulatory agencies. In this study, we calibrated two in vitro P-gp inhibition models: vesicular uptake of N-methyl-quinidine (NMQ) in MDR1 vesicles and bidirectional transport (BDT) of digoxin in Lilly Laboratories Cell Porcine Kidney 1 cells overexpressing MDR1 (LLC-MDR1) using a total of 48 P-gp inhibitor and noninhibitor drugs and digoxin DDI data from 70 clinical studies. Refined thresholds were derived using receiver operating characteristic analysis, and their predictive performance was compared with the decision frameworks proposed by regulatory agencies and selected reference. Furthermore, the impact of various IC50 calculation methods and nonspecific binding of drugs on DDI prediction was evaluated. Our studies suggest that the concentration of inhibitor based on highest approved dose dissolved in 250 ml divided by IC50(I2/IC50) is sufficient to predict P-gp related intestinal DDIs. IC50 obtained from vesicular inhibition assay with a refined threshold of I2/IC50 ≥ 25.9 provides comparable predictive power over those measured by net secretory flux and efflux ratio in LLC-MDR1 cells. We therefore recommend vesicular P-gp inhibition as our preferred method given its simplicity, lower variability, higher assay throughput, and more direct estimation of in vitro kinetic parameters, rather than BDT assay. SIGNIFICANCE STATEMENT: This study has conducted comprehensive calibration of two in vitro P-gp inhibition models: uptake in MDR1 vesicles and bidirectional transport in LLC-MDR1 cell monolayers to predict DDIs. This study suggests that IC50s obtained from vesicular inhibition with a refined threshold of I2/IC50 ≥ 25.9 provide comparable predictive power over those in LLC-MDR1 cells. Therefore, vesicular P-gp inhibition is recommended as the preferred method given its simplicity, lower variability, higher assay throughput, and more direct estimation of in vitro kinetic parameters.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Digoxina , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico/fisiologia , Digoxina/metabolismo , Suínos , Transcitose
4.
J Lipid Res ; 57(12): 2150-2162, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27707816

RESUMO

SREBP cleavage-activating protein (SCAP) is a key protein in the regulation of lipid metabolism and a potential target for treatment of dyslipidemia. SCAP is required for activation of the transcription factors SREBP-1 and -2. SREBPs regulate the expression of genes involved in fatty acid and cholesterol biosynthesis, and LDL-C clearance through the regulation of LDL receptor (LDLR) and PCSK9 expression. To further test the potential of SCAP as a novel target for treatment of dyslipidemia, we used siRNAs to inhibit hepatic SCAP expression and assess the effect on PCSK9, LDLR, and lipids in mice and rhesus monkeys. In mice, robust liver Scap mRNA knockdown (KD) was achieved, accompanied by dose-dependent reduction in SREBP-regulated gene expression, de novo lipogenesis, and plasma PCSK9 and lipids. In rhesus monkeys, over 90% SCAP mRNA KD was achieved resulting in approximately 75, 50, and 50% reduction of plasma PCSK9, TG, and LDL-C, respectively. Inhibition of SCAP function was demonstrated by reduced expression of SREBP-regulated genes and de novo lipogenesis. In conclusion, siRNA-mediated inhibition of SCAP resulted in a significant reduction in circulating PCSK9 and LDL-C in rodent and primate models supporting SCAP as a novel target for the treatment of dyslipidemia.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipídeos/sangue , Proteínas de Membrana/genética , Pró-Proteína Convertase 9/genética , RNA Interferente Pequeno/genética , Receptores de LDL/genética , Animais , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Hipolipemiantes/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipogênese , Fígado/enzimologia , Macaca mulatta , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Pró-Proteína Convertase 9/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de LDL/metabolismo , Transdução de Sinais , Sinvastatina/farmacologia , Proteínas de Ligação a Elemento Regulador de Esterol/genética , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo
5.
Drug Metab Dispos ; 43(6): 851-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25813937

RESUMO

Inhibition of hepatic transporters such as organic anion transporting polypeptides (OATPs) 1B can cause drug-drug interactions (DDIs). Determining the impact of perpetrator drugs on the plasma exposure of endogenous substrates for OATP1B could be valuable to assess the risk for DDIs early in drug development. As OATP1B orthologs are well conserved between human and monkey, we assessed in cynomolgus monkeys the endogenous OATP1B substrates that are potentially suitable to assess DDI risk in humans. The effect of rifampin (RIF), a potent inhibitor for OATP1B, on plasma exposure of endogenous substrates of hepatic transporters was measured. From the 18 biomarkers tested, RIF (18 mg/kg, oral) caused significant elevation of plasma unconjugated and conjugated bilirubin, which may be attributed to inhibition of cOATP1B1 and cOATP1B3 based on in vitro to in vivo extrapolation analysis. To further evaluate whether cynomolgus monkeys are a suitable translational model to study OATP1B-mediated DDIs, we determined the inhibitory effect of RIF on in vitro transport and pharmacokinetics of rosuvastatin (RSV) and atorvastatin (ATV). RIF strongly inhibited the uptake of RSV and ATV by cOATP1B1 and cOATP1B3 in vitro. In agreement with clinical observations, RIF (18 mg/kg, oral) significantly decreased plasma clearance and increased the area under the plasma concentration curve (AUC) of intravenously administered RSV by 2.8- and 2.7-fold, and increased the AUC and maximum plasma concentration of orally administered RSV by 6- and 10.3-fold, respectively. In contrast to clinical findings, RIF did not significantly increase plasma exposure of either intravenous or orally administered ATV, indicating species differences in the rate-limiting elimination pathways.


Assuntos
Indutores das Enzimas do Citocromo P-450/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacocinética , Moduladores de Transporte de Membrana/efeitos adversos , Microssomos Hepáticos/efeitos dos fármacos , Modelos Biológicos , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Administração Oral , Animais , Bilirrubina/análogos & derivados , Bilirrubina/sangue , Bilirrubina/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Indutores das Enzimas do Citocromo P-450/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Interações Medicamentosas , Células HEK293 , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Injeções Intravenosas , Macaca fascicularis , Masculino , Moduladores de Transporte de Membrana/administração & dosagem , Taxa de Depuração Metabólica , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/metabolismo , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Distribuição Aleatória , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Especificidade da Espécie
6.
Fitoterapia ; 177: 106077, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38906387

RESUMO

The screening of based target compounds supported by LC/MS, MS/MS and Global Natural Products Social (GNPS) used to identify the compounds 1-10 of Butea monsperma. They were evaluated in human malignant embryonic rhabdomyoma cells (RD cells) infected with Human coronavirus OC43 (HCoV-OC43) and showed significant inhibitory activity. Target inhibition tests showed that compounds 6 and 8 inhibited the proteolytic enzyme 3CLpro, which is widely present in coronavirus and plays an important role in the replication process, with an effective IC50 value. The study confirmed that dioxymethylene of compound 8 may be a key active fragment in inhibiting coronavirus (EC50 7.2 µM, SI > 139.1). The results have led to identifying natural bioactive compounds for possible inhibiting HCoV-OC43 and developing drug for Traditional Chinese Medicine (TCM).

7.
Mol Pharm ; 10(8): 3103-11, 2013 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-23819524

RESUMO

Activated macrophages play a significant role in initiation and progression of inflammatory diseases and may serve as the basis for the development of targeted diagnostic methods for imaging sites of inflammation. Folate receptor beta (FR-ß) is differentially expressed on activated macrophages associated with inflammatory disease states yet is absent in either quiescent or resting macrophages. Because folate binds with high affinity to FR-ß, development of folate directed imaging agents has proceeded rapidly in the past decade. However, reports of PET based imaging agents for use in inflammatory conditions remain limited. To investigate whether FR-ß expressing macrophages could be exploited for PET based inflammatory imaging, two separate folate-targeted PET imaging agents were developed, 4-[(18)F]-fluorophenylfolate and [(68)Ga]-DOTA-folate, and their ability to target activated macrophages were examined in a rodent inflammatory paw model. We further compared inflamed tissue uptake with 2-[(18)F]fluoro-2-deoxy-d-glucose ([(18)F]-FDG). microPET analysis demonstrated that both folate-targeted PET tracers had higher uptake in the inflamed paw compared to the control paw. When these radiotracers were compared to [(18)F]-FDG, both folate PET tracers had a higher signal-to-noise ratio (SNR) than [(18)F]-FDG, suggesting that folate tracers may be superior to [(18)F]-FDG in detecting diseases with an inflammatory component. Moreover, both folate-PET imaging agents also bind to FR-α which is overexpressed on multiple human cancers. Therefore, these folate derived PET tracers may also find use for localizing and staging FR(+) cancers, monitoring response to therapy, and for selecting patients for tandem folate-targeted therapies.


Assuntos
Fluordesoxiglucose F18 , Ácido Fólico , Inflamação/diagnóstico , Tomografia por Emissão de Pósitrons , Animais
8.
Environ Sci Pollut Res Int ; 30(36): 85708-85720, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37392296

RESUMO

The objective of this study is to examine how digital finance influences renewable energy performance in China. Empirical data from China between 2007 and 2019 is used to evaluate the relationship among these variables. The study uses two techniques, quantile regression (QR) and generalized methods of moments (GMM), to draw empirical conclusions. The results reveal that digital finance significantly influences the renewable energy performance, ecological growth, and financial performance of cities in China. Specifically, digital finance accounts for 45.92% of the variation in renewable energy indicators, 27.60% in ecological growth, and 24.39% in the improved financial performance of renewable energy at the city level. The study also observes that the city-level score for digital finance, renewable energy, and other indicators is heterogeneous in movement. Factors contributing to this heterogeneity include high population (16.05%), access to digital banking (23.11%), province-level renewable energy performance (39.62%), household financial stability (22.04%), and household renewable energy literacy (8.47%). Based on these findings, the study recommends practical implications for key stakeholders.


Assuntos
Alfabetização , Movimento , China , Cidades , Energia Renovável , Desenvolvimento Econômico
9.
Environ Sci Pollut Res Int ; 30(57): 120552-120563, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37940828

RESUMO

This study inquiry examines the vital role that Fintech and green bonds play in ensuring that China generates clean energy in a comprehensive manner, taking into consideration the mechanisms of green investment risk. This paper provides exciting new insights on the link between financial technology (Fintech), green bonds, and China's clean energy economy by using a reliable approach and doing an in-depth data analysis. The findings provide a significant contribution to our understanding of how Fintech may help enable financing for renewable energy projects by using digital platforms, mobile payment technologies, and blockchain technology to boost investor confidence and accessibility to funds for clean energy projects. This aspect of green bonds is emphasized since the study highlights the importance of sustainable energy generation. The need of proactive regulatory frameworks that are able to adjust to the shifting Fintech and green bond markets while supporting good policies, motivating factors, and efficient risk management procedures is emphasized in the research. The study contributes to the enlightenment of academic discourse, focuses efforts at policymaking, and gives knowledge that is helpful to people who are working to promote a greener and more sustainable future.


Assuntos
Análise de Dados , Investimentos em Saúde , Humanos , China , Conhecimento , Energia Renovável , Tecnologia , Desenvolvimento Econômico
10.
J Pharm Sci ; 112(3): 771-778, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36240862

RESUMO

Imaging is commonly used as a characterization method in the pharmaceuticals industry, including for quantifying subvisible particles in solid and liquid formulations. Extracting information beyond particle size, such as classifying morphological subpopulations, requires some type of image analysis method. Suggested methods to classify particles have been based on pre-determined morphological features or use supervised training of convolutional neural networks to learn image representations in relation to ground truth labels. Complications arising from highly complex morphologies, unforeseen classes, and time-consuming preparation of ground truth labels, are some of the challenges faced by these methods. In this work, we evaluate the application of a self-supervised contrastive learning method in studying particle images from therapeutic solutions. Unlike with supervised training, this approach does not require ground truth labels and representations are learned by comparing particle images and their augmentations. This method provides a fast and easily implementable tool of coarse screening for morphological attribute assessment. Furthermore, our analysis shows that in cases with relatively balanced datasets, a small subset of an image dataset is sufficient to train a convolutional neural network encoder capable of extracting useful image representations. It is also demonstrated that particle classes typically observed in protein solutions administered by pre-filled syringes emerge as separated clusters in the encoder's embedding space, facilitating performing tasks such as training weakly-supervised classifiers or identifying the presence of new subpopulations.


Assuntos
Redes Neurais de Computação , Aprendizado de Máquina Supervisionado , Processamento de Imagem Assistida por Computador/métodos , Composição de Medicamentos , Proteínas
11.
Front Endocrinol (Lausanne) ; 12: 641722, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122330

RESUMO

Non-invasive beta cell function measurements may provide valuable information for improving diabetes diagnostics and disease management as the integrity and function of pancreatic beta cells have been found to be compromised in Type-1 and Type-2 diabetes. Currently, available diabetes assays either lack functional information or spatial identification of beta cells. In this work, we introduce a method to assess the function of beta cells in the non-human primate pancreas non-invasively with MRI using a Gd-based zinc(II) sensor as a contrast agent, Gd-CP027. Additionally, we highlight the role of zinc(II) ions in the paracrine signaling of the endocrine pancreas via serological measurements of insulin and c-peptide. Non-human primates underwent MRI exams with simultaneous blood sampling during a Graded Glucose Infusion (GGI) with Gd-CP027 or with a non-zinc(II) sensitive contrast agent, gadofosveset. Contrast enhancement of the pancreas resulting from co-release of zinc(II) ion with insulin was observed focally when using the zinc(II)-specific agent, Gd-CP027, whereas little enhancement was detected when using gadofosveset. The contrast enhancement detected by Gd-CP027 increased in parallel with an increased dose of infused glucose. Serological measurements of C-peptide and insulin indicate that Gd-CP027, a high affinity zinc(II) contrast agent, potentiates their secretion only as a function of glucose stimulation. Taken in concert, this assay offers the possibility of detecting beta cell function in vivo non-invasively with MRI and underscores the role of zinc(II) in endocrine glucose metabolism.


Assuntos
Meios de Contraste/farmacologia , Gadolínio/química , Células Secretoras de Insulina/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Zinco/química , Albuminas/química , Animais , Feminino , Glucose/metabolismo , Insulina , Íons , Macaca mulatta , Masculino , Pâncreas/metabolismo , Peptídeos/química , Primatas/metabolismo , Ligação Proteica
12.
Hepatogastroenterology ; 57(98): 326-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20583436

RESUMO

Autoimmune hepatitis is a chronic liver disease of unknown etiology. The diagnosis is based on the exclusion of other liver diseases such as drug-induced liver disease, alcohol liver disease, viral liver diseases and so on, characterizing by elevation of transaminases, hypergammaglobulinemia, auto antibodies and the histological features of interface hepatitis and plasma cells infiltration. However, deep cholestatic jaundice as the initial presentation, with elevated serum transaminases one month later, is rare in autoimmune hepatitis. We described a case of type 1 autoimmune hepatitis with deep cholestatic jaundice and hyperbilirubinemia as the initial predominant manifestation. It demonstrated that the cholestasis can also occur as the initial predominant syndrome in autoimmune hepatitis and respond well to the treatment with the glycyrrhizin and ursodeoxycholic acid.


Assuntos
Hepatite Autoimune/complicações , Icterícia Obstrutiva/complicações , Anti-Inflamatórios/uso terapêutico , Biópsia por Agulha , Colagogos e Coleréticos/uso terapêutico , Diagnóstico Diferencial , Feminino , Ácido Glicirrízico/uso terapêutico , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/tratamento farmacológico , Humanos , Icterícia Obstrutiva/diagnóstico , Icterícia Obstrutiva/tratamento farmacológico , Testes de Função Hepática , Pessoa de Meia-Idade , Ácido Ursodesoxicólico/uso terapêutico
13.
J Acoust Soc Am ; 125(3): 1666-78, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19275324

RESUMO

The growth of the vocal tract (VT) is known to be non-uniform insofar as there are regional differences in anatomic maturation. This study presents quantitative anatomic data on the growth of the oral and pharyngeal portions of the VT from 605 imaging studies for individuals between birth and 19 years. The oral (horizontal) portion of the VT was segmented into lip-thickness, anterior-cavity-length, oropharyngeal-width, and VT-oral, and the pharyngeal (vertical) portion of the VT into posterior-cavity-length, and nasopharyngeal-length. The data were analyzed to determine growth trend, growth rate, and growth type (neural or somatic). Findings indicate differences in the growth trend of segments/variables analyzed, with significant sex differences for all variables except anterior-cavity-length. While the growth trend of some variables displays prepubertal sex differences at specific age ranges, the importance of such localized differences appears to be masked by overall growth rate differences between males and females. Finally, assessment of growth curve type indicates that most VT structures follow a combined/hybrid (somatic and neural) growth curve with structures in the vertical plane having a predominantly somatic growth pattern. These data on the non-uniform growth of the vocal tract reveal anatomic differences that contribute to documented acoustic differences in prepubertal speech production.


Assuntos
Laringe , Imageamento por Ressonância Magnética , Faringe , Tomografia Computadorizada por Raios X , Acústica , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Laringe/anatomia & histologia , Laringe/diagnóstico por imagem , Laringe/crescimento & desenvolvimento , Masculino , Orofaringe/anatomia & histologia , Orofaringe/diagnóstico por imagem , Orofaringe/crescimento & desenvolvimento , Faringe/anatomia & histologia , Faringe/diagnóstico por imagem , Faringe/crescimento & desenvolvimento , Adulto Jovem
14.
Huan Jing Ke Xue ; 40(7): 3324-3330, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854734

RESUMO

By conducting field positioning experiments, we studied the development trend of Cd pollution in a typical paddy system. The samples of atmospheric deposition and irrigation water were collected monthly from November 2015 to November 2018 during which fertilizer, soil, and rice samples were also collected. The Cd concentration in the samples was monitored and analyzed to conduct research on the balance between Cd inputs and outputs in a typical paddy system in Hunan Province. The results suggest that through irrigation water, atmospheric deposition and fertilizer, the average annual input of Cd in the paddy field system is 8.735 g·(hm2·a)-1, of which atmospheric deposition, the major source, accounts for 69.15%-82.04% of the total input, with an average of 76.61%. This is followed by irrigation water and fertilizer, respectively, accounting for 12.62%-23.66% and 5.34%-7.19%, with an average of 16.94% and 6.45%, respectively. Through surface runoff, soil infiltration and the rice harvest of the aboveground portion, the annual average output of Cd contained in the paddy system is 7.093 g·(hm2·a)-1. Rice harvest accounts for 85.27%-95.02% of the total output, with an average of 89.69%; surface runoff accounted for 4.57%-13.96% of the total output, with an average of 9.41%; and soil infiltration accounted for 0.41%-1.51% of the total output, with an average of 0.90%. The study indicates that Cd contained in paddy systems in Central Hunan exhibits a net input, and the soil Cd pollution is increasing as a result. Straw returning and straw removal have an important impact on the soil Cd balance, and straw removal can slow the trend of soil Cd pollution accumulation.


Assuntos
Cádmio/análise , Oryza , Poluentes do Solo/análise , Irrigação Agrícola , Fertilizantes , Solo/química
15.
Huan Jing Ke Xue ; 39(1): 406-414, 2018 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965708

RESUMO

Pot experiments were used to study the differences of Cd uptake and accumulation in double-cropping rice in typical soil types. To analyze the soil availability of Cd (DTPA-Cd) in soils and the Cd accumulation in double-cropping rice at different growth stages of the rice, we conducted pot experiments that selected the yellow clayey soil (paddy soil developed from plate shaley parent materials) and the granitic sandy soil (paddy soil developed from granitic parent materials). Exogenous Cd was added with gradients of 0, 0.5, 1.0, 2.0, 5.0, and 10.0 mg·kg-1. Results showed that, during the rice growth period, the available Cd in the yellow clayey soil was higher than that in the granitic sandy soil, and the difference was significant (P<0.01). This showed that the content of Cd in rice (roots, shoots, leaves, rice shells, and brown rice) increased along with the treatment level and with the extension of the rice growth period. The accumulation characteristics of Cd in rice grains and other tissues of rice indicated differences between two seasons and two soil types, that is, late rice was higher in Cd than was early rice, and reddish yellow clayey soil was higher in Cd than granitic sandy soil. Significant positive linear correlations were found between the effective contents of Cd in soils and those in rice tissues (roots, shoots, leaves, and brown rice). The prediction model of Cd in rice and the characteristic equation for rice accumulation of Cd were applied to calculate the critical values of Cd:0.98 mg·kg-1 for early rice and 0.83 mg·kg-1 for late rice in reddish yellow clayey soil, and 0.86 mg·kg-1 for early rice and 0.56 mg·kg-1 for late rice in granitic sandy soil. These threshold values are higher than the National Standards given in "farmland environmental quality evaluation standards for edible agricultural products (HJ 332-2006)." The soil security threshold values and the soil environmental capacities of the two different parent materials varied greatly; therefore, different environmental quality standards may be formulated and different measures may be needed to control Cd pollution in different parent materials.


Assuntos
Cádmio/análise , Oryza/crescimento & desenvolvimento , Poluentes do Solo/análise , Solo/química , Agricultura , Oryza/química
16.
Acad Radiol ; 14(9): 1102-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17707318

RESUMO

RATIONALE AND OBJECTIVES: Head circumference (HC) is an important developmental measure used both clinically and in research. This paper advances a method to estimate HC from imaging studies when a direct HC-tape measurement cannot be secured. Unlike former approaches, the model takes into account the fact that growth is nonlinear, and that HC growth rates are sexually dimorphic. MATERIALS AND METHODS: A model was first established based on published data to represent the normative HC growth curves for males and females. Then, using magnetic resonance (MR) studies of 90 subjects (birth to 18 years), a linear method to estimate HC was adapted to take into account the nonlinear and sex-specific HC normative growth curves. The accuracy of this model was tested prospectively by comparing the estimated HC with HC measurements from twelve computed tomography (CT) studies using the perimeter tracing of oblique slices that correspond to the plane at which a clinical HC-tape measurement is secured. RESULTS: Prospective comparison of estimated HC to HC tracings using a paired t-test validates that the model provides an accurate estimation of the measured HC (t=-.845, p=0.416 overall; t=.54, p=.615 for females and t=-2.34, p=.066 for males). DISCUSSION: HC can be calculated indirectly from imaging studies. The model is highly predictive of HC-tape measurements and provides the physician or scientist with a very reliable method to secure HC when it is not feasible to secure the HC-tape measurement.


Assuntos
Antropometria/métodos , Tamanho Corporal , Cabeça/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Modelos Biológicos , Pediatria/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Simulação por Computador , Feminino , Humanos , Imageamento Tridimensional/métodos , Lactente , Recém-Nascido , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
SAGE Open Med ; 5: 2050312117700057, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28491305

RESUMO

INTRODUCTION: Despite the widespread use of the mouse transverse aortic constriction heart failure model, there are no reports on the characterization of the standard-of-care agent carvedilol in this model. METHODS: Left ventricular pressure overload was produced in mice by transverse aortic constriction between the innominate and left common carotid arteries. Carvedilol was administered at multiple dose levels (3, 10 and 30 mg/kg/day per os; yielding end-study mean plasma concentrations of 0.002, 0.015 and 0.044 µM, respectively) in a therapeutic design protocol with treatment initiated after the manifestation of left ventricular remodeling at 3 weeks post transverse aortic constriction and continued for 10 weeks. RESULTS: Carvedilol treatment in transverse aortic constriction mice significantly decreased heart rate and left ventricular dP/dt (max) at all dose levels consistent with ß-adrenoceptor blockade. The middle dose of carvedilol significantly decreased left ventricular weight, whereas the higher dose decreased total heart, left and right ventricular weight and wet lung weight compared to untreated transverse aortic constriction mice. The higher dose of carvedilol significantly increased cardiac performance as measured by ejection fraction and fractional shortening and decreased left ventricular end systolic volume consistent with the beneficial effect on cardiac function. End-study plasma sST-2 and Gal-3 levels did not differ among sham, transverse aortic constriction control and transverse aortic constriction carvedilol groups. Plasma brain natriuretic peptide concentrations were elevated significantly in transverse aortic constriction control animals (~150%) compared to shams in association with changes in ejection fraction and heart weight and tended to decrease (~30%, p = 0.10-0.12) with the mid- and high-dose carvedilol treatment. CONCLUSION: A comparison of carvedilol hemodynamic and structural effects in the mouse transverse aortic constriction model versus clinical use indicates a strong agreement in effect profiles preclinical versus clinical, providing important translational validation for this widely used animal model. The present plasma brain natriuretic peptide biomarker findings support the measurement of plasma natriuretic peptides in the mouse transverse aortic constriction model to extend the translational utility of the model.

18.
PLoS One ; 11(7): e0160055, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27467585

RESUMO

Chlamydia trachomatis is among the most prevalent of sexually transmitted diseases. While Chlamydia infection is a reportable event and screening has increased over time, enhanced surveillance has not resulted in a reduction in the rate of infections, and Chlamydia infections frequently recur. The development of a preventative vaccine for Chlamydia may be the only effective approach for reducing infection and the frequency of pathological outcomes. Current vaccine research efforts involve time consuming and/or invasive approaches for assessment of disease state, and MRI presents a clinically translatable method for assessing infection and related pathology both quickly and non-invasively. Longitudinal T2-weighted MRI was performed over 63 days on both control or Chlamydia muridarum challenged mice, either with or without elementary body (EB) immunization, and gross necropsy was performed on day 65. A scoring system was developed to assess the number of regions affected by Chlamydia pathology and was used to document pathology over time and at necropsy. The scoring system documented increasing incidence of pathology in the unimmunized and challenged mice (significantly greater compared to the control and EB immunized-challenged groups) by 21 days post-challenge. No differences between the unchallenged and EB immunized-challenged mice were observed. MRI scores at Day 63 were consistently higher than gross necropsy scores at Day 65, although two of the three groups of mice showed no significant differences between the two techniques. In this work we describe the application of MRI in mice for the potential evaluation of disease pathology and sequelae caused by C. muridarum infection and this technique's potential for evaluation of vaccines for Chlamydia.


Assuntos
Infecções por Chlamydia/diagnóstico por imagem , Modelos Animais de Doenças , Animais , Infecções por Chlamydia/microbiologia , Células HeLa , Humanos , Imageamento por Ressonância Magnética , Camundongos
19.
Bone ; 73: 32-41, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25482211

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease resulting in joint inflammation, pain, and eventual bone loss. Bone loss and remodeling caused by symmetric polyarthritis, the hallmark of RA, is readily detectable by bone mineral density (BMD) measurement using micro-CT. Abnormalities in these measurements over time reflect the underlying pathophysiology of the bone. To evaluate the efficacy of anti-rheumatic agents in animal models of arthritis, we developed a high throughput knee and ankle joint imaging assay to measure BMD as a translational biomarker. A bone sample holder was custom designed for micro-CT scanning, which significantly increased assay throughput. Batch processing 3-dimensional image reconstruction, followed by automated image cropping, significantly reduced image processing time. In addition, we developed a novel, automated image analysis method to measure BMD and bone volume of knee and ankle joints. These improvements significantly increased the throughput of ex vivo bone sample analysis, reducing data turnaround from 5 days to 24 hours for a study with 200 rat hind limbs. Taken together, our data demonstrate that BMD, as quantified by micro-CT, is a robust efficacy biomarker with a high degree of sensitivity. Our innovative approach toward evaluation of BMD using optimized image acquisition and novel image processing techniques in preclinical models of RA enables high throughput assessment of anti-rheumatic agents offering a powerful tool for drug discovery.


Assuntos
Artrite Reumatoide/patologia , Densidade Óssea , Colágeno/administração & dosagem , Microtomografia por Raio-X/métodos , Animais , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/prevenção & controle , Modelos Animais de Doenças , Feminino , Ratos , Ratos Endogâmicos Lew
20.
Chin Med J (Engl) ; 126(2): 260-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23324274

RESUMO

BACKGROUND: Lupus hepatitis is yet to be characterized based on its clinical features and is often difficult to differentially diagnose from other liver diseases. We aimed to elucidate clinical, histopathological and immunopathological features of lupus hepatitis and to evaluate primarily the effectiveness of liver immunopathological manifestations on differential diagnosis of lupus hepatitis from other liver diseases. METHODS: A retrospective study was performed to analyze clinical features of lupus hepatitis in 47 patients out of 504 inpatients with systemic lupus erythematosus (SLE) in First Affiliated Hospital of Sun Yat-sen University, China from May 2006 to July 2009, and to evaluate the association between lupus hepatitis and SLE activity. Additionally, liver histopathological changes by hematoxylin and eosin (HE) staining and immunopathological changes by direct immunofluorescence test in 10 lupus hepatitis cases were analyzed and compared to those in 16 patients with other liver diseases in a prospective study. RESULTS: Of 504 SLE patients, 47 patients (9.3%) were diagnosed to have lupus hepatitis. The prevalence of lupus hepatitis in patients with active SLE was higher than that in those with inactive SLE (11.8% vs. 3.2%, P < 0.05). The incidence of hematological abnormalities in patients with lupus hepatitis was higher than that in those without lupus hepatitis (40.4% vs. 21.7%, P < 0.05), such as leucocytes count (2.92×10(9)/L vs. 5.48×10(9)/L), platelets count (151×10(9)/L vs. 190×10(9)/L), serum C3 and C4 (0.34 g/L vs. 0.53 g/L; 0.06 g/L vs. 0.09 g/L) (P < 0.05); 45 of 47 (95.7%) lupus hepatitis patients showed 1 upper limit of normal (ULN) < serum ALT level < 5 ULN. The liver histopathological features in patients with lupus hepatitis were miscellaneous and non-specific, similar to those in other liver diseases, but liver immunopathological features showed positive intense deposits of complement 1q in 7/10 patients with lupus hepatitis and negative complement 1q deposits in all patients with other liver diseases (Fisher's exact test, P = 0.011). CONCLUSIONS: Lupus hepatitis was not infrequent in active SLE patients which would be one of the indices indicating SLE activity. Positive intense deposit of complement 1q in liver may be a characteristic immunopathological feature of lupus hepatitis, which provides a new way to differentially diagnose lupus hepatitis from other liver diseases.


Assuntos
Hepatite Autoimune/imunologia , Hepatite Autoimune/patologia , Lúpus Eritematoso Sistêmico/complicações , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Complemento C1q/análise , Feminino , Hepatite Autoimune/etiologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA