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71.
We describe the antinociceptive and anti-inflammatory properties of citronellol (CT) in rodents. CT, a monoterpene alcohol, is a naturally occurring monoterpene compound prevalent in essential oils of various aromatic plant species, such as Cymbopogon citratus. In mice, when evaluated against acetic-acid-induced abdominal writhing, CT (25, 50 and 100?mg/kg, i.p.) reduced (P?相似文献   
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The ability of cells to undergo cellular transitions, in particular, to switch between epithelial and mesenchymal states, might be highly advantageous during the progression of carcinoma. Using histological and immunohistochemical techniques, we here show that the injection into mice of spontaneously transformed NIH-3T3 cells generated fusocellular sarcomas, whereas NIH-3T3 cells that had been transformed by culturing with plasma from colorectal cancer patients gave rise to tumors that phenotypically resembled the carcinomas of the original cancer patients. Thus, plasma from cancer patients is able to transform NIH-3T3 fibroblasts into malignant epithelial-like cells, suggesting that such cells might undergo mesenchymal to epithelial transition during plasma-induced transformation.  相似文献   
74.
OBJECTIVES: To evaluate the bonding interface in experimentally weakened roots reinforced with adhesive restorative materials and quartz fibre posts, varying the light-exposure time of the composite resin used for root reinforcement. METHODS: Twelve extracted human maxillary incisors teeth were used. The crowns were removed and the roots were endodontically treated. After post space preparation, the roots were assigned to four groups. The thickness of the root dentine was reduced and adhesively restored with composite resin light-activated through a translucent fibre post for either 40s (group 1), 80s (group 2) or 120s (group 3). In the case of control (group 4), the roots were not weakened. One day after post cementation, the specimens were sectioned transversally in three slices and processed for scanning electron microscopic analysis to observe bonding interface formation, quality of the hybrid layer and density of resin tags using a four-step scale method. RESULTS: Formation of a hybrid layer and resin tags were evident in all groups. There was no statistically (p>0.05) significant difference between the regions analysed in each group (Friedman test) and between groups in each section depth (Kruskal-Wallis test). Furthermore, comparison of the flared/reinforced groups showed that the different times used for composite resin cure did not affect the results significantly (Kruskal-Wallis test, p=0.2139). CONCLUSIONS: Different light-exposure times used for composite resin polymerisation during root canal reinforcement did not affect significantly the formation and quality of the dentine/adhesive/composite resin bonding interface.  相似文献   
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Background

Exposure to arsenic (As) concentrations in drinking water > 150 μg/L has been associated with risk of diabetes and cardiovascular disease, but little is known about the effects of lower exposures.

Objective

This study aimed to examine whether moderate As exposure, or indicators of individual As metabolism at these levels of exposure, are associated with cardiometabolic risk.

Methods

We analyzed cross-sectional associations between arsenic exposure and multiple markers of cardiometabolic risk using drinking-water As measurements and urinary As species data obtained from 1,160 adults in Chihuahua, Mexico, who were recruited in 2008–2013. Fasting blood glucose and lipid levels, the results of an oral glucose tolerance test, and blood pressure were used to characterize cardiometabolic risk. Multivariable logistic, multinomial, and linear regression were used to assess associations between cardiometabolic outcomes and water As or the sum of inorganic and methylated As species in urine.

Results

After multivariable adjustment, concentrations in the second quartile of water As (25.5 to < 47.9 μg/L) and concentrations of total speciated urinary As (< 55.8 μg/L) below the median were significantly associated with elevated triglycerides, high total cholesterol, and diabetes. However, moderate water and urinary As levels were also positively associated with HDL cholesterol. Associations between arsenic exposure and both dysglycemia and triglyceridemia were higher among individuals with higher proportions of dimethylarsenic in urine.

Conclusions

Moderate exposure to As may increase cardiometabolic risk, particularly in individuals with high proportions of urinary dimethylarsenic. In this cohort, As exposure was associated with several markers of increased cardiometabolic risk (diabetes, triglyceridemia, and cholesterolemia), but exposure was also associated with higher rather than lower HDL cholesterol.

Citation

Mendez MA, González-Horta C, Sánchez-Ramírez B, Ballinas-Casarrubias L, Hernández Cerón R, Viniegra Morales D, Baeza Terrazas FA, Ishida MC, Gutiérrez-Torres DS, Saunders RJ, Drobná Z, Fry RC, Buse JB, Loomis D, García-Vargas GG, Del Razo LM, Stýblo M. 2016. Chronic exposure to arsenic and markers of cardiometabolic risk: a cross-sectional study in Chihuahua, Mexico. Environ Health Perspect 124:104–111; http://dx.doi.org/10.1289/ehp.1408742  相似文献   
78.
The relationship between metallic cast crowns and tensile strength according to cement types submitted to thermocycling was studied. Seventy-two metallic crowns were cast with Verabond II Ni-Cr alloy and cemented in standardized preparations with 10 masculine tapering. Three types of finishing line (45-degree chamfered, 20-degree bevel shoulder and right shoulder) were made with diamond burs on bovine teeth. Twenty-four metallic crowns in each group were randomly subdivided into three subgroups of 8 samples each according to the cement used: SS White zinc phosphate cement, Vitremer resin-modified glass ionomer cement, and Rely X resin cement and were submitted to thermocycling. Retention was evaluated according to tensile load required to displace the metallic cast crowns from tooth preparations with an Instron testing machine. ANOVA and Tukey's test showed a statistically significant difference among luting materials, with greater results for Rely X resin cement (24.9 kgf) followed by SS White zinc phosphate cement (13.3 kgf) and Vitremer resin-modified glass ionomer cement (10.1 kgf). The finishing line types did not influence the tensile resistance of the crowns fixed with the three cements. Increased tensile resistance of metallic crowns fixed on bovine teeth was obtained with resin cement, independent of the finishing line types.  相似文献   
79.
The phenomenon of circulating nucleic acids in plasma and serum (CNAPS) has opened many new research lines, which may be framed within two areas of translational research: the development of new techniques for noninvasive prenatal diagnosis; and the study of the pathobiology of many diseases, particularly of cancer. The detection, quantization, and quality analysis of CNAPS have increasingly been found to be interesting and useful in the diagnosis and management of a number of pathologies, at least as complementary tools. The high potential value of CNAPS and the lack of knowledge about their origin and implications have aroused a great interest in many researchers, especially in the last two decades. In fact, in 1999, about 30 published studies focused on this issue, whereas in 2011 it was more than 100.  相似文献   
80.
INTRODUCTION: Most cancer deaths are due to the development of metastases and this phenomenon is still a hard challenge for researchers. A number of theories have tried to unravel the metastatic machinery, but definitive results that link the evidence with conventional concepts of metastatic disease remain to be reported. AREAS COVERED: Considerable evidence suggests interactions between tumor cells and host cells that might be essential for tumor progression and metastasis. Most such evidence is suggestive of fusion phenomena, but some suggest the transfer of cell-free DNA (cfDNA). Such evidence is often ignored or overlooked in the assessment and management of malignancy. In this article, we review the available evidence for the importance of cell fusion and cfDNA in metastasis, and we present some preliminary data that support the hypothesis that tumor progression might be based not only on the division of tumor cells but also on the transformation of normal cells. EXPERT OPINION: Future success in the search for cancer therapies will surely require advances in our knowledge of the pathways of tumor invasion by unexpected mechanisms. Thus, no well supported evidence for roles of cell-free nucleic acids and fusion of cells or of cells with vesicles should be ignored.  相似文献   
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