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1.
Microbiol Spectr ; 12(2): e0120923, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38197656

RESUMO

Proteus mirabilis can transfer transposons, insertion sequences, and gene cassettes to the chromosomes of other hosts through SXT/R391 integrative and conjugative elements (ICEs), significantly increasing the possibility of antibiotic resistance gene (ARG) evolution and expanding the risk of ARGs transmission among bacteria. A total of 103 strains of P. mirabilis were isolated from 25 farms in China from 2018 to 2020. The positive detection rate of SXT/R391 ICEs was 25.2% (26/103). All SXT/R391 ICEs positive P. mirabilis exhibited a high level of overall drug resistance. Conjugation experiments showed that all 26 SXT/R391 ICEs could efficiently transfer to Escherichia coli EC600 with a frequency of 2.0 × 10-7 to 6.0 × 10-5. The acquired ARGs, genetic structures, homology relationships, and conservation sequences of 26 (19 different subtypes) SXT/R391 ICEs were investigated by high-throughput sequencing, whole-genome typing, and phylogenetic tree construction. ICEPmiChnHBRJC2 carries erm (42), which have never been found within an SXT/R391 ICE in P. mirabilis, and ICEPmiChnSC1111 carries 19 ARGs, including clinically important cfr, blaCTX-M-65, and aac(6')-Ib-cr, making it the ICE with the most ARGs reported to date. Through genetic stability, growth curve, and competition experiments, it was found that the transconjugant of ICEPmiChnSCNNC12 did not have a significant fitness cost on the recipient bacterium EC600 and may have a higher risk of transmission and dissemination. Although the transconjugant of ICEPmiChnSCSZC20 had a relatively obvious fitness cost on EC600, long-term resistance selection pressure may improve bacterial fitness through compensatory adaptation, providing scientific evidence for risk assessment of horizontal transfer and dissemination of SXT/R391 ICEs in P. mirabilis.IMPORTANCEThe spread of antibiotic resistance genes (ARGs) is a major public health concern. The study investigated the prevalence and genetic diversity of integrative and conjugative elements (ICEs) in Proteus mirabilis, which can transfer ARGs to other hosts. The study found that all of the P. mirabilis strains carrying ICEs exhibited a high level of drug resistance and a higher risk of transmission and dissemination of ARGs. The analysis of novel multidrug-resistant ICEs highlighted the potential for the evolution and spread of novel resistance mechanisms. These findings emphasize the importance of monitoring the spread of ICEs carrying ARGs and the urgent need for effective strategies to combat antibiotic resistance. Understanding the genetic diversity and potential for transmission of ARGs among bacteria is crucial for developing targeted interventions to mitigate the threat of antibiotic resistance.


Assuntos
Conjugação Genética , Proteus mirabilis , Proteus mirabilis/genética , Filogenia , Resistência a Múltiplos Medicamentos , Elementos de DNA Transponíveis , Antibacterianos/farmacologia , Escherichia coli/genética , Medição de Risco
2.
BMC Ophthalmol ; 23(1): 402, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803347

RESUMO

PURPOSE: To evaluate the early corneal remodeling and its influencing factors after Small incision lenticule extraction (SMILE) for moderate and high myopia. METHODS: This was a retrospective study. Pre- and post-operative (1 week and 1, 3, 6 months) corneal volume (CV), mean keratometry (Km), and corneal thickness (CT) were measured by Scheimpflug tomography. CT at the central, thinnest point, and on concentric circles of 2, 4, and 6 mm diameter was recorded to assess corneal thickness spatial profile (CTSP) and percentage of thickness increase (PTI) in the moderate and high myopia groups, and to explore possible influencing factors. RESULTS: After SMILE, the peripheral CT decreased in the moderate myopia group and central corneal thickness (CCT) increased in the high myopia group at 1 month compared to 1 week (all P < 0.05). The CV, Km and CT were significantly increased at 3 months compared to 1 month (all P < 0.05), but there was no significant change at 6 months compared to 3 months for both groups (all P > 0.05). Patients with high myopia showed greater corneal thickness changes (△CT) and higher PTI than moderate myopia (all P < 0.05). Regression analysis revealed that in addition to refraction, peripheral PTI was negatively correlated with CCT in the moderate myopia group (4 mm: ß = -0.023, P = 0.001; 6 mm: ß = -0.050, P < 0.001), as well as in the high myopia group (4 mm: ß = -0.038, P < 0.001; 6 mm: ß = -0.094, P < 0.001). Moreover, peripheral PTI in the moderate myopia group was negatively correlated with age (4 mm: ß = -0.071, P = 0.003; 6 mm: ß = -0.162, P < 0.001). CONCLUSIONS: After SMILE, the CV, Km, and CTSP showed dynamic changes in the early stage, which stabilized after 3 months. Compared to the moderate myopia group, the high myopia group experienced slower corneal stabilization. The change in PTI at 6 months after SMILE may be related to higher preoperative refraction, thinner CCT and younger age.


Assuntos
Cirurgia da Córnea a Laser , Miopia , Humanos , Substância Própria/diagnóstico por imagem , Substância Própria/cirurgia , Estudos Retrospectivos , Acuidade Visual , Cirurgia da Córnea a Laser/métodos , Córnea/diagnóstico por imagem , Córnea/cirurgia , Miopia/cirurgia , Lasers de Excimer/uso terapêutico
3.
Genes (Basel) ; 14(10)2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37895253

RESUMO

Han is the largest of China's 56 ethnic groups and the most populous ethnic group in the world. The Luzhou region is located in southwest China, at the junction of three provinces. The unique historical factors contribute to the genetic polymorphism information. Short tandem repeats (STRs) are highly polymorphic, but the polymorphism of the Y chromosomal STRs (Y-STRs) loci in the Luzhou region is still unclear. It is of great significance to provide Y-STRs genetic data for the Han population from the Luzhou areas of southwest China. A total of 910 unrelated male individuals of the Han population from the Luzhou area were recruited, and 24 Y-STRs were analyzed. The population structure and phylogenetic relationships were compared with those of another 11 related Han populations. A total of 893 different haplotypes were achieved from 910 samples, of which 877 (98.21%) haplotypes were unique. Haplotype diversity and discrimination were 0.999956 and 0.981319, respectively. The lowest genetic diversity of DYS437 is 0.4321, and the highest genetic diversity of DYS385a/b is 0.9642. Pair-to-pair genetic distance and relative probability values indicate that Luzhou Han people are close to Sichuan Han people, Guangdong Han people, and Hunan Han people, which is consistent with geographical distribution, historical influence, and economic development. The 24 Y-STR markers of the southwest Luzhou Han population were highly polymorphic, which provided us with genetic polymorphism information and enriched the population genetic database. Therefore, it is of great value to our forensic applications and population genetics research.


Assuntos
Cromossomos Humanos Y , População do Leste Asiático , Humanos , Masculino , Filogenia , Cromossomos Humanos Y/genética , Polimorfismo Genético , Repetições de Microssatélites/genética , China
4.
Endocr Pract ; 29(6): 428-435, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37004871

RESUMO

OBJECTIVE: To develop and validate a risk stratification system for the prediction of malignancy in partially cystic thyroid nodules (PCTNs). METHODS: We retrospectively reviewed the sonography data of patients with PCTNs from 2 medical centers-Hangzhou Traditional Chinese Medicine Hospital and Hangzhou First People's Hospital-from January 2020 to December 2021. The independent risk factors for malignant PCTNs were evaluated using the univariate and multivariate logistic regression analyses. The nomogram prediction efficiency was assessed using the area under the curve and calibration curves. The decision curve analysis was used to determine the clinical value of the predictive model. RESULTS: A total of 285 patients were enrolled in this retrospective study, and of 301 PCTNs, 242 were benign and 59 were malignant. Younger age, hypoechoic, irregular margin, and microcalcifications were found to be the independent risk factors for malignant PCTNs. The area under the curve, sensitivity, and specificity were 0.860, 77.1%, and 84.7% in the training data set and 0.897, 91.7%, and 87.0% in the external validation data set, respectively. The total point of nomogram was >161, which showed the best to predict malignancy in PCTNs. CONCLUSION: Our findings demonstrated that the risk stratification system for the assessment of PCTNs showed good prediction capacities.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Estudos Retrospectivos , Ultrassonografia , Medição de Risco , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Nomogramas
5.
Pest Manag Sci ; 78(3): 1018-1028, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34773351

RESUMO

BACKGROUND: Bactrocera dorsalis is a devastating pest on fruits and vegetables because the adult female is the key factor that determines the population density of offspring and the degree of host damage. Unfortunately, there is still a lack of effective female attractants for behavioral control. Males of B. dorsalis fed on methyl eugenol (ME) were shown to be more sexually attracted to females and, therefore, were more successful in mating over ME-deprived males. RESULTS: In the current study, we demonstrated that (E)-coniferyl alcohol (E-CF), one of the ME metabolites in males, was highly attractive to sexually-mature females in laboratory bioassays. During the dusk courtship period, mature females showed the highest response to E-CF. However, there were no significant differences in olfactory responses to E-CF between virgin and mated mature females. Moreover, no obvious signs and symptoms of toxicity or death were observed in mice during a 14-day acute oral toxicity test. Toxicologically, no significant changes were observed in body weight, water intake, food consumption and absolute and relative organ weights between control and treated groups of healthy-looking mice, implying that E-CF could be regarded as non-toxic. Furthermore, cytotoxicity assessment revealed that E-CF was non-toxic against human fetal lung fibroblast 1 (HFL1), human breast cancer (MDA-MB-231), mouse embryonic hepatocytes (BNL-CL.2) and Spodoptera frugiperda ovary (SF-9) cell lines. CONCLUSIONS: E-CF proved to be an effective, promising and eco-friendly lure to B. dorsalis females. Therefore, this study may facilitate the development of novel control strategies against B. dorsalis in the field.


Assuntos
Tephritidae , Animais , Drosophila , Feminino , Masculino , Camundongos , Fenóis , Reprodução
6.
Appl Psychol Health Well Being ; 12(4): 967-982, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33016617

RESUMO

BACKGROUND: A large number of the population experienced panic during the pandemic of the coronavirus disease 2019 (COVID-19) in China. The current study explored the trajectory of panic and its associated factors to develop promising strategies for controlling the global spread of COVID-19 and improving the mental health emergency management. METHODS: A total of 812 unmarried adults (aged from 18 to 42 years, M = 23.3, SD = 3.45) from all over China participated online in our investigation. A Growth Mixture Model (GMM) was developed and analysed. RESULTS: Three classes of trajectories for panic were identified: the "continuous decline group (CDG)", the "continuous low group (CLG)," and the "continuous high group (CHG)". With reference to the CDG, people in the CHG were more sensitive to social factors. With reference to the CDG, people in the CLG were more likely to possess some of the following traits: being men, in Hubei Province (center of the pandemic), with a lower income, and less sensitive towards social factors and individual factors. With reference to the CLG, people in the CHG were more likely to be women, located outside of Hubei Province, and more sensitive to social factors, family factors, and individual factors. CONCLUSION: Social factors, family factors, and individual factors predicted the different trajectories of panic.


Assuntos
Ansiedade/epidemiologia , Pânico/classificação , Pessoa Solteira/estatística & dados numéricos , Fatores Socioeconômicos , Adolescente , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Fatores Sexuais , Fatores Sociais , Adulto Jovem
7.
Front Oncol ; 9: 479, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293962

RESUMO

Purpose: Sorafenib and sunitinib are extensively used as first-line medications for metastatic renal cell carcinoma (mRCC). This meta-analysis was conducted to assess the antitumor efficacy, toxicity, and costs of the two drugs among mRCC patients. Materials and methods: PubMed, ScienceDirect, Scopus, Web of Science, Ovid MEDLINE, the Cochrane Library, Embase, and Google Scholar were searched for eligible articles. The endpoints consisted of progression-free survival (PFS), overall survival (OS), objective response rate (ORR), adverse effects (AEs), and per-patient-per-month (PPPM) costs. Results: We included 14 studies with 2,925 patients. Both drugs were valid for treating mRCC with equivalent PFS [hazard ratio (HR) = 0.98, 95% confidence interval (CI): 0.88-1.10, P = 0.74] and disease control rates [DCRs; risk ratio (RR) = 1.03, 95% CI: 0.98-1.08, P = 0.28], but sunitinib had a better OS (HR = 1.10, 95% CI: 1.01-1.20, P = 0.04) and higher ORR (HR = 0.66, 95% CI: 0.45-0.97, P = 0.03) than sorafenib. Furthermore, sunitinib induced more incidences of severe hematologic AEs (anemia, neutropenia, and thrombocytopenia) and stomatitis/mucositis than sorafenib. In the subanalysis, Asian patients treated with sorafenib reported a longer PFS than those treated with sunitinib (HR = 0.87, 95% CI: 0.83-0.90, P = 0.01), and European patients treated with sunitinib had a longer OS than those treated with sorafenib (HR = 1.17, 95% CI: 1.01-1.30, P = 0.04). Moreover, the pooled results of the high-quality studies reported a higher ORR with sunitinib than with sorafenib, and medium-quality studies showed a longer OS with sunitinib than with sorafenib. Conclusions: Sunitinib has more benefits (longer OS and better ORR) than sorafenib as a first-line therapy for mRCC. However, sunitinib has higher toxicity than sorafenib. Sorafenib might be more suitable than sunitinib among Asian patients, and sunitinib might be superior to sorafenib in European patients. Nevertheless, more large-scale, high-quality studies are required.

8.
Sci Total Environ ; 657: 781-791, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30677943

RESUMO

Human activities and regional land development have caused intense interference to ecosystems. With rapid development of economy and urgent needs of life quality improvements in China, sustainable ecosystem management is crucial for national ecological civilization construction. However, few studies have focused on supply-demand patterns of ecosystem services on a national scale in China. The aim of this study was to analyze the spatial-temporal patterns and changes in the supply-demand of ecosystem services and to explore their interactive relationship in the context of economic development and urbanization drivers. The ecosystem services provision index (ESPI) and land development index (LDI) were proposed to indicate the supply and demand for ecosystem services. The results indicated that the Low supply-High demand (L-H) pattern accounted for 3.27% of the total land area in China and was mainly concentrated in developed regions and some capital cities, where 28.95% of the total population and 51.93% of the country's GDP was generated in 2015. The spatial imbalance in the supply-demand of ecosystem services was obvious. From 2000 to 2015, the imbalance was shrinking, and regions with negative changes in supply-demand patterns were declining. During 2000-2008, there was an obvious transformation from Low supply-Low demand (L-L) to High supply-Low demand (H-L), which accounted for 12.44% of the total land area due to Grain for Green and other ecological protection policies. The proportion of ecological land to total land area, vegetation cover and elevation were significantly correlated with the supply of ecosystem services. In the meantime, ESPI was negatively correlated with LDI in most regions in China. There were also regional differences in their relationships. The rapid economic growth and the intensive land development resulted in a more significant decrease in ESPI in the developed regions than that in the undeveloped North and Northeast China. The results of this study could contribute to sustainable ecosystem management and decision-making for Chinese ecological civilization construction.

9.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 40(5): 630-636, 2018 Oct 30.
Artigo em Chinês | MEDLINE | ID: mdl-30404694

RESUMO

Objective To investigate the associations of socioeconomic factors,nutrients intake,and gut microbiota of healthy pregnant women in the third trimester with gestational weight gain (GWG).Methods We recruited 98 pregnant women in the third trimester who had received antenatal care in the Department of Obstetrics Gynecology,Peking Union Medical College Hospital from October,2015 to May,2016. We collected socioeconomic information through a structured questionnaire covering age,ethnicity,height,pre-pregnancy weight,and education. Nutritional status of these pregnant women was assessed by a 24-hour dietary intake recall. The participants were provided with collective tubes for faecal sample collection at home;their weight before the delivery was recorded. The pre-pregnancy weight and GWG were classified according to World Health Organization body mass index (BMI) standard for adults and the Institute of Medicine GWG guidelines (2009),respectively. The gut microbiota of the participants were analyzed using a whole-metagenome shotgun sequencing method.Results Insufficient and excessive GWG accounted for 15.3% and 50.0% of the cohort,respectively. Appropriate GWG level was associated with intakes of fat (F=3.113,P=0.049),carbohydrates (F=3.750,P=0.027),and dietary fiber (F=4.499,P=0.014) but not with age (F=2.495,P=0.088),ethnicity (Χ 2=0.065,P=0.968),education (Χ 2=0.827,P=0.661),or pre-pregnancy BMI (F=0.121,P=0.887). Compared with the participants with appropriate GWG,those with excessive GWG had significantly higher abundance of Akkermansia muciniphila,Atopobium parvulum,and Alistipes indistinctus as well as lower abundance of Lactobacillus rhamnosus,Weissella unclassified,Eubacterium ventriosum,Ruminococcus torques,and Bacteroides uniformis. Compared with the participants with appropriate GWG,those with insufficient GWG had significantly higher abundance of Dialister invisus,Alistipes unclassified,Peptoniphilus harei,Escherichia unclassified,Parvimonas unclassified,Campylobacter ureolyticus,Lactobacillus crispatus,and Fusobacterium nucleatum and lower abundance of Eubacterium ventriosum.Conclusions Abnormal GWG is common in pregnant women. GWG is significantly associated with gut microbiota as well as with nutritional factors including fat,carbohydrate,and dietary fiber intake.


Assuntos
Dieta , Microbioma Gastrointestinal , Ganho de Peso na Gestação , Fatores Socioeconômicos , Índice de Massa Corporal , Feminino , Humanos , Nutrientes , Gravidez , Terceiro Trimestre da Gravidez
10.
J Telemed Telecare ; 23(1): 3-13, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27269795

RESUMO

Background Remote home management is a new healthcare model that uses information technology to enhance patients' self-management of disease in a home setting. This study is designed to identify the effects of remote home management on patients with chronic kidney disease (CKD). Methods A comprehensive search of PubMed, MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials was performed in January 2015. The reference listings of the included articles in this review were also manually examined. Randomized controlled trials (RCTs) designed to evaluate the effects of remote home management on patients with CKD were included. Results Eight trials were identified. The results of this study suggest that the quality of life (QOL) enabled by remote home management was higher than typical care in certain dimensions. However, the effects of remote home management on blood pressure (BP) remain inconclusive. The studies that assessed health service utilization demonstrated a significant decrease in hospital readmission, emergency room visits, and number of days in the hospital. Another favorable result of this study is that regardless of their gender, age or nationality, patients tend to comply with remote home management programs and the use of related technologies. Conclusions The available data indicate that remote home management may be a novel and effective disease management strategy for improving CKD patients' QOL and influencing their attitudes and behaviors. And, relatively little is known about BP and cost-effectiveness, so future research should focus on these two aspects for the entire population of patients with CKD.


Assuntos
Serviços de Assistência Domiciliar/organização & administração , Insuficiência Renal Crônica/terapia , Autocuidado/métodos , Telemedicina/métodos , Monitorização Ambulatorial da Pressão Arterial/métodos , Análise Custo-Benefício , Humanos , Tempo de Internação , Readmissão do Paciente , Qualidade de Vida
11.
Ethn Health ; 22(2): 184-195, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27706949

RESUMO

OBJECTIVE: Prostate cancer mortality rates have decreased over recent decades, but racial disparities in prostate cancer survival still present as a serious challenge. These disparities may be impacted by age; in fact, African-American men younger than age 65 have prostate cancer mortality rates nearly three times greater than that of White men. Therefore, a systematic literature review was conducted in Medline and EMBASE databases focusing on articles comparing survival and mortality rates for prostate cancer patients across age and race. DESIGN: Articles included were based on the following criteria: (1) included African-American and White prostate cancer patients residing in the US; (2) measured racial disparities across distinct age categories with at least one category below and one above age 65; and (3) addressed racial disparities in terms of overall survival or mortality. RESULTS: Twenty eight articles compared survival and mortality disparities between African-American and White prostate cancer patients across different age categories. Of the 28 articles, 19 articles (68%) showed disparities decreased with age, 8 articles (29%) showed disparities constant with age, and 1 article (3%) showed disparities increased with age. CONCLUSIONS: More often the survival and mortality gap between African-American and White prostate cancer patients decreases with age. Additional studies are needed to elucidate other factors that may influence racial disparities in prostate cancer patients. These results provide insight into the racial disparities in prostate cancer and suggest more resources should be directed towards decreasing the disparity gap in younger prostate cancer patients.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Disparidades nos Níveis de Saúde , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/mortalidade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , População Branca/estatística & dados numéricos
12.
ChemSusChem ; 8(11): 1901-7, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25916895

RESUMO

The development of a green system to solubilize cellulose from raw biomass is important, yet it is challenging because of the insolubility of cellulose in most solvents. Herein, a green NaCl-H2 O system is developed in which NaCl significantly enhances the dissolution and depolymerisation of cellulose from raw biomass. Nearly all the cellulose in the selected biomass types was dissolved and degraded into oligomers with molecular weights of 200-400 Da under relatively mild conditions. Cl(-) could interact strongly with the end OH group of the glucose unit in a 1:1 ratio, which resulted in the enhanced breaking of both inter- and intramolecular hydrogen bonds. In particular, the intermolecular hydrogen bond with an FTIR band at approximately v=3200 cm(-1) was disrupted significantly by Cl(-) . The FTIR band for a hydrogen bond between hemicellulose and lignin might appear at v=1636 cm(-1) , whereas this bond could be almost totally broken under hydrothermal conditions at 220 °C.


Assuntos
Biomassa , Celulose/química , Polimerização , Cloreto de Sódio/química , Água/química , Análise Custo-Benefício , Solubilidade , Solventes/química , Zea mays/química
13.
Appl Opt ; 50(29): 5647-54, 2011 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-22015358

RESUMO

This paper reports the development and characterization of a low-cost thin unimorph deformable mirror (DM) driven by positive voltage. The developed DM consists of both an inner actuator array and an outer ring actuator, which works two drive modes: the inner actuator array is used for aberration correction, while the outer ring actuator is used to generate an overall defocus bias. An analytical model based on the theory of plates and shells is studied for predicting the behavior of the developed DM. Measurement results indicate that dual direction maximum defocus deformations of the developed DM are -14.3 and 14.9 µm, respectively, and the resonant frequency is 1.8 kHz. The root-mean-square deformation of the mirror surface after correction is better than λ/20 for λ=633 nm. The replication of Zernike mode shapes up to the fifth order demonstrates that this developed DM is satisfactory for low-order aberration correction.

14.
J Cell Mol Med ; 15(4): 837-49, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20497492

RESUMO

Angiogenesis is essential to tumour progression and a precise evaluation of angiogenesis is important for tumour early diagnosis and treatment. The quantitative and dynamic in vivo assessment of tumour angiogenesis can be achieved by molecular magnetic resonance imaging (mMRI). Vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFRs) are the main regulatory systems in angiogenesis and have been used as hot targets for radionuclide-based molecular imaging. However, little research has been accomplished in targeting VEGF/VEGFRs by mMRI. In our study, we aimed to assess the expression of VEGFR2 in C6 gliomas by using a specific molecular probe with mMRI. The differential uptake of the probe conjugated to anti-VEGFR2 monoclonal antibody, shown by varied increases in T(1) signal intensity during a 2 hr period, demonstrated the heterogeneous expression of VEGFR2 in different tumour regions. Microscopic fluorescence imaging, obtained for the biotin group in the probe with streptavidin-Cy3, along with staining for cellular VEGFR2 levels, laminin and CD45, confirmed the differential distribution of the probe which targeted VEGFR2 on endothelial cells. The angiogenesis process was also assessed using magnetic resonance angiography, which quantified tumour blood volume and provided a macroscopic view and a dynamic change of the correlation between tumour vasculature and VEGFR2 expression. Together these results suggest mMRI can be very useful in assessing and characterizing the expression of specific angiogenic markers in vivo and help evaluate angiogenesis associated with tumour progression.


Assuntos
Glioma/metabolismo , Imageamento por Ressonância Magnética/métodos , Imagem Molecular/métodos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Biotina/metabolismo , Western Blotting , Linhagem Celular Tumoral , Glioma/irrigação sanguínea , Glioma/patologia , Imuno-Histoquímica , Angiografia por Ressonância Magnética , Masculino , Sondas Moleculares/metabolismo , Neovascularização Patológica/metabolismo , Ácido Pentético/metabolismo , Ratos , Ratos Endogâmicos F344 , Reprodutibilidade dos Testes , Soroalbumina Bovina/metabolismo
15.
J Magn Reson Imaging ; 31(4): 796-806, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20373422

RESUMO

PURPOSE: To demonstrate that OKN007, a disulfonyl derivative of phenyl-tert-butyl nitrone (PBN), has anti-glioma activity in the clinically relevant C6 rat glioma model using multi-parametric magnetic resonance imaging. MATERIALS AND METHODS: Twenty-one rats were intracerebrally implanted with C6 cells and administered OKN007 or kept as controls. Animals were monitored with MRI at 7 Tesla (T), using morphologic, diffusion-weighted and perfusion imaging, followed by histology and Western blots of angiogenesis and inflammatory markers. RESULTS: OKN007 was found to decrease tumor volumes and increase survival. The glioma tissues of OKN007-treated rats were found to have longitudinal apparent diffusion coefficients (ADC(z)) of 0.76 +/- 0.06 x 10(-3) mm(2)/s, similar to the contralateral tissue and significantly smaller than untreated gliomas (0.97 +/- 0.13 x 10(-3) mm(2)/s). They had higher perfusion rates (66 +/- 4 mL/100 g.min) than untreated gliomas (26 +/- 7 mL/100 g.min). All examined molecular markers were decreased in OKN007-treated rat gliomas, compared with elevated levels in untreated rats. CONCLUSION: MRI assessment was successfully used to monitor a decrease in tumor growth, and corresponding alterations in ADC and perfusion rates in rat C6 gliomas treated with the anti-glioma agent, OKN007.


Assuntos
Antineoplásicos/uso terapêutico , Benzenossulfonatos/uso terapêutico , Glioma/tratamento farmacológico , Iminas/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Animais , Encéfalo/patologia , Linhagem Celular Tumoral , Difusão , Modelos Animais de Doenças , Ensaios de Seleção de Medicamentos Antitumorais , Inflamação , Transplante de Neoplasias , Perfusão , Ratos , Fatores de Tempo , Resultado do Tratamento
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