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31.
Growing evidence indicating the critical modulator roles of microRNAs (miRNAs) involved in prostate cancer (PCa) metastasis that holds great promise as therapeutic targets. Herein, we transfected the miR-622 mimic into PC3 cells and evaluated the effects of this interference on these tumour cells' growth and the expression of specific metastatic genes. Transfecting of miR-622 mimic and inhibitor, negative control (NC) inhibitor and NC was established using Lipofectamine 2000. The mRNA levels of miR-622 and metastatic genes were evaluated using the qRT-PCR and Western blot. Cytotoxic effects of miR-622 were assessed by MTT. Apoptosis was detected using an ELISA cell death assay kit. miR-622 is down-regulated in PC3 cells. As expected, cell viability effects after transfection were described as miR-622 inhibitor >NC and NC inhibitor >miR-622 mimic (p < .01). Importantly, we showed that transfected miR-622 mimic could enhance the apoptosis of PC3 cells, while transfected miR-622 inhibitor could decrease cell apoptosis (p < .01). Furthermore, miR-622 overexpression could increase significantly down-regulated the MMP2, MMP9, CXCR-4, c-Myc and K-Ras expression levels. Findings demonstrate a novel mechanism by which miR-622 modulates PCa cells' metastasis by targeting metastatic genes. These data confirm the tumour-suppressive function of miR-622 in PCa cells by enhancing apoptosis and reducing metastasis.  相似文献   
32.

Background

Bismuth shield has been recently introduced for radiation protection of patient radiosensitive organs such as breast during chest CT with image diagnosis capability. The purpose of this study was to evaluate the dose reduction and image quality conserve using new bismuth-silicon composite shields during chest CT.

Materials and methods

Scans were performed on a PMMA phantom using a 6-slice MDCT system. Dose reduction was calculated by placing ion-chamber in the 12?o’clock position for breast dose measuring. Chest CT scans was performed with and without new bismuth composite shields 10% by 0.5?mm and 1?mm thicknesses. Image quality was assessed by CT numbers and noise evaluation.

Results

The results of using bismuth composite shields induced to dose reduction to 7% and 12% for 0.5?mm and 1?mm thicknesses, respectively. As a result of the using 0.5?mm and 1?mm bismuth composite shields, the mean CT numbers and noise increased by a factor of 0.01 and 0.02 and also from 0.08 to 0.13, respectively. Significant dose decline was measured and no relevant noise was found.

Conclusion

Results showed that new bismuth-silicon composite shields have good potential to breast dose reduction with smallest noise for diagnosis in chest CT.  相似文献   
33.
神经系统疾病儿童的血铅水平调查:单中心初步研究   总被引:1,自引:0,他引:1  
目的:儿童铅中毒具有很大的潜在危害。慢性低水平铅暴露会导致学习障碍及行为问题,如腹痛,失眠,多动,生长发育落后,听力损失,上肢无力。该研究旨在调查神经系统疾病儿童的血铅水平,并与健康儿童作比较。方法:100名患有神经系统疾病的1~10岁儿童作为研究对象。100名年龄和性别匹配的健康儿童作为对照。采用火焰原子吸收光谱法检测血铅含量。结果:神经系统疾病组儿童的平均血铅含量显著高于对照组,差异有显著性 (113.2±47.5 μg/L vs 84.7±38.0 μg/L; P<0.01)。神经系统疾病组和对照组分别有44%和19%的儿童血铅超标(>100 μg/L)。结论:儿童血铅水平增高可能与神经系统疾病有关。建议对患神经系统疾病的儿童常规作血铅测定。[中国当代儿科杂志,2009,11(11):873-876]  相似文献   
34.
35.

Objective

This study aimed to develop and test the validity of a risk score to be used as a simple tool to identify those children at high risk of sonographic non-alcoholic fatty liver disease (NAFLD).

Methods

This cross-sectional study was conducted among 962 participants aged 6–18 years in Isfahan, Iran. They consisted of three groups of nearly equal number of normal-weight, overweight and obese individuals. Coefficients of the logistic regression models were used to assign a score value for each variable and the composite sonographic NAFLD risk score was calculated as the sum of those scores. Performance of model was assessed by receiver operating characteristic (ROC) curve procedure.

Findings

Data of 931 participants was included in the analysis. The sonographic findings of 16.8% of participants were compatible with NAFLD. Age, sex, body mass index, waist circumference and serum triglycerides level were diagnosed as factors associated with NAFLD. The risk score was calculated as 50 for sonographic NAFLD.

Conclusion

This study, to the best of our knowledge is the first of its kind in the pediatric age group, focuses on predicting sonographic NAFLD from easily-measured factors. It may suggest an association of hypertriglyceridemic-waist phenotype with NAFLD in the pediatric age group.  相似文献   
36.
Oral osmotic devices including an elementary osmotic pump (EOP) are efficient systems for the delivery of drugs with high/moderately water-solublility. In this study we designed a new type of EOP for the efficient delivery of poorly water-soluble and practically insoluble drugs. In this system, called swellable elementary osmotic pump (SEOP), drug is released from the delivery orifice in the form of a very fine dispersion of drug in gel which is ready for dissolution and absorption. Factors affecting the release of drug from the SEOP containing a poorly water-soluble drug, nifedipine, were explored extensively. To this end, effect of swelling and wetting agents, orifice size, concentration of osmotic agent, and hydrophobic plasticizer were investigated. Interestingly, in the absence or low concentration of a hydrophobic plasticizer (caster oil), the osmotic devices did not retain their integrity in dissolution media. Caster oil in concentration of > 1% was necessary for tablets to retain their integrity during dissolution process. A zero-order release kinetics for nifedipine was achieved following the effective optimization of the concentrations of swelling agent, osmotic agent, wetting agent, and also size of orifice and membrane thickness in SEOP. The zero-order release lasted for 10 hr at pH 6.8 dissolution medium. The designed SEOP is suggested as an efficient controlled delivery system for oral delivery of a poorly water soluble drug such as nifedipine.  相似文献   
37.
We present here the characteristics of an in situ forming hydrogel prepared from carboxymethyl chitosan and oxidized carboxymethyl cellulose for interventional therapies. Gelation, owing to the formation of Schiff bases, occurred both with and without the presence of a radiographic contrast agent. The hydrogel exhibited a highly porous internal structure (pore diameter 17 ± 4 μm), no cytotoxicity to human umbilical vein endothelial cells, hemocompatibility with human blood, and degradability in lysozyme solutions. Drug release from hydrogels loaded with a sclerosant, tetracycline, was measured at pH 7.4, 6 and 2 at 37 °C. The results showed that tetracycline was more stable under acidic conditions, with a lower release rate observed at pH 6. An anticancer drug, doxorubicin, was loaded into the hydrogel and a cumulative release of 30% was observed over 78 h in phosphate-buffered saline at 37 °C. Injection of the hydrogel precursor through a 5-F catheter into a fusiform aneurysm model was feasible, leading to complete filling of the aneurysmal sac, which was visualized by fluoroscopy. The levels of occlusion by hydrogel precursors (1.8% and 2.1%) and calibrated microspheres (100–300 μm) in a rabbit renal model were compared. Embolization with hydrogel precursors was performed without clogging and the hydrogel achieved effective occlusion in more distal arteries than calibrated microspheres. In conclusion, this hydrogel possesses promising characteristics potentially beneficial for a wide range of vascular intervention procedures that involve embolization and drug delivery.  相似文献   
38.

Introduction

Our aim was to compare changes of body mass index (BMI) and waist circumference (WC) curves of Iranian children by comparing the results of two national surveys of a surveillance program, i.e. CASPIAN-I (2003–2004) and CASPIAN-III (2009–2010). The second objective was to evaluate the prevalence of obesity, overweight and underweight among 10–18-year-old Iranian children and adolescents.

Material and methods

This study was performed among students who were selected by multistage random cluster sampling from urban and rural areas of 27 provinces of Iran, as part of a national survey of school student high risk behavior entitled CASPIAN-III, conducted in 2009–2010.

Results

We evaluated 5088 school students (50.2% boys). In rural areas, underweight was more common in boys and overweight and obesity in girls. In urban areas underweight and obesity were more common in boys, whereas overweight was more common in girls. The highest prevalence of underweight (23.5%) was seen in students aged 13 years and the lowest (11.4%) in those aged 18 years. Underweight was significantly more common in rural than in urban areas (22.1% vs. 15.8%, respectively, p < 0.0001) and overweight/obesity was more common in urban than in rural areas. Compared with the findings in 2003–2004, the overall prevalence of elevated body mass index (16.6%) including obesity (9.1%) and overweight (7.5%) as well as underweight (17.5%) increased from 2003 to 2010.

Conclusions

In recent years, the double burden of nutritional disorders has increased among Iranian children and adolescents, especially in rural areas. This change may be related to epidemiologic transition, notably in terms of nutrition transition and rapid changes in lifestyle habits. This finding is an important issue for policy-makers for interventional preventive programs.  相似文献   
39.

Objectives

Chronic apical periodontitis (CAP) appears to be a risk factor for coronary heart disease. The aims of the study were to estimate the significance of AP for the atherosclerotic burden and to examine the potential effect of endodontic treatment.

Materials and methods

The whole-body computed tomography (CT) examinations of 531 patients with a mean age of 50?±?15.7 years were evaluated retrospectively. The atherosclerotic burden of the abdominal aorta was quantified using a calcium scoring method. The parameters of periodontitis were measured using the CT scan.

Results

The patients had a total of 11,191 teeth. The volume of the aortic atherosclerotic burden for patients with at least one CAP lesion was 0.32?±?0.92 ml, higher than for patients with no CAP (0.17?±?0.51 ml; p?p?p?Conclusions CAP correlated positively with the aortic atherosclerotic burden. In regression models, CAP without endodontic treatment was found to be an important factor, not however apical radiolucencies in teeth with endodontic treatment.

Clinical relevance

Further research is needed to clarify the possible clinical significance of these associations.  相似文献   
40.
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