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21.
Gene expression profiling in animal models exposed to cigarette mainstream smoke (CS) shapes up as a promising tool for investigating the molecular mechanisms involved in the onset and development of CS-related disease and may aid in the identification of disease candidate genes. Here we report on differential gene expression in lungs of rats exposed for 2, 7, and 13 weeks to 300 and 600 microg total particulate matter/l CS with sacrifice 2, 6, or 20 h after the last exposure. Regarding antioxidant and xenobiotic-metabolizing (phase I/II) enzymes, a stereotypic, mostly transient, expression pattern of differentially expressed genes was observed after each exposure period. The expression patterns were generally dose dependent for antioxidant and phase II genes and not dose dependent for phase I genes at the CS concentrations tested. However, with increasing length of exposure, there was a distinct, mostly sustained and dose-sensitive, expression of genes implicated in innate and adaptive immune responses, clearly pointing to an emerging inflammatory response. Notably, this inflammatory response included the expression of lung disease-related genes not yet linked to CS exposure, such as galectin-3, arginase 1, and chitinase, as well as genes encoding proteolytic enzymes. Finally, our experiments also revealed a CS exposure-dependent shift in the cyclical expression of genes involved in controlling the circadian rhythm. Altogether, these results provide further insight into the molecular mechanisms of CS-dependent disease onset and development and thus may also be useful for defining CS-specific molecular biomarkers of disease.  相似文献   
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Single wall carbon nanotubes (SWCNTs) are advanced materials with the potential for a myriad of diverse applications, including biological technologies and large‐scale usage with the potential for environmental impacts. SWCNTs have been exposed to developing organisms to determine their effects on embryogenesis, and results have been inconsistent arising, in part, from differing material quality, dispersion status, material size, impurity from catalysts and stability. For this study, we utilized highly purified SWCNT samples with short, uniform lengths (145 ± 17 nm) well dispersed in solution. To test high exposure doses, we microinjected > 500 µg ml–1 SWCNT concentrations into the well‐established embryogenesis model, Xenopus laevis, and determined embryo compatibility and subcellular localization during development. SWCNTs localized within cellular progeny of the microinjected cells, but were heterogeneously distributed throughout the target‐injected tissue. Co‐registering unique Raman spectral intensity of SWCNTs with images of fluorescently labeled subcellular compartments demonstrated that even at regions of highest SWCNT concentration, there were no gross alterations to subcellular microstructures, including filamentous actin, endoplasmic reticulum and vesicles. Furthermore, SWCNTs did not aggregate and localized to the perinuclear subcellular region. Combined, these results suggest that purified and dispersed SWCNTs are not toxic to X. laevis animal cap ectoderm and may be suitable candidate materials for biological applications. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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OBJECTIVE: To determine if pelvic organ prolapse reduction decreases cystometric leak point pressure. STUDY DESIGN: A retrospective review was performed of women with pelvic organ prolapse points Aa, Ba or C > or = -1 cm that leaked with and without vaginal support (barrier testing) during multichannel urodynamic investigation (N=44). An analysis of the mean and difference between leak point pressure (LPP) (vesicle pressure) with and without prolapse reduction was used to determine significance. RESULTS: Among 460 possible study subjects, 15% (71/460) leaked only with and 4% (17/460) only without prolapse reduction. Among the 44 women who leaked both with and without prolapse reduction, prolapse reduction was associated with a mean decrease in LPP of 16.1 cm H2O (95% CI 7.4-24.7, p = 0.0005). CONCLUSION: Reduction of pelvic organ prolapse is associated with a mean decrease in LPP of 16.1 cm H2O.  相似文献   
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A laparoscopic approach may be used to improve the surgical management of advanced ovarian cancer.  相似文献   
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From 2017 to 2019, several vaccine-like recombinant strains of lumpy skin disease virus (LSDV) were discovered in Kazakhstan and neighbouring regions of Russia and China. Shortly before their emergence, the authorities in Kazakhstan launched a mass vaccination campaign with the Neethling-based Lumpivax vaccine. Since none of the other countries in the affected region had used a homologous LSDV vaccine, it was soon suspected that the Lumpivax vaccine was the cause of these unusual LSDV strains. In this study, we performed a genome-wide molecular analysis to investigate the composition of two Lumpivax vaccine batches and to establish a possible link between the vaccine and the recent outbreaks. Although labelled as a pure Neethling-based LSDV vaccine, the Lumpivax vaccine appears to be a complex mixture of multiple CaPVs. Using an iterative enrichment/assembly strategy, we obtained the complete genomes of a Neethling-like LSDV vaccine strain, a KSGP-like LSDV vaccine strain and a Sudan-like GTPV strain. The same analysis also revealed the presence of several recombinant LSDV strains that were (almost) identical to the recently described vaccine-like LSDV strains. Based on their InDel/SNP signatures, the vaccine-like recombinant strains can be divided into four groups. Each group has a distinct breakpoint pattern resulting from multiple recombination events, with the number of genetic exchanges ranging from 126 to 146. The enormous divergence of the recombinant strains suggests that they arose during seed production. The recent emergence of vaccine-like LSDV strains in large parts of Asia is, therefore, most likely the result of a spillover from animals vaccinated with the Lumpivax vaccine.  相似文献   
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Cerano is a municipality of the Province of Novara (North-West Italy). To assess the morbidity associated to its proximity to a petrochemical plant, standardized incidence ratios (SIRs) of oncological pathologies in the period 2003–2009 were calculated based on age-sex specific rates for the district of the Local Health Authority of Novara (ASL13) and the main regional city of Turin. For all cancers combined, men showed a significant higher risk (SIR: 1.21; 95% CI: 1.02–1.40) compared to the ASL13 population; significantly lower risks for both men and women were observed in comparison to the Turin population. Among women, a significant excess of mesothelioma cancers was reported; a significantly higher risk for lympho-haematopoietic pathologies was also observed compared to the Turin population only. Several other cancers have significantly lower rates in Cerano for both men and women. Despite some studies’ limitations, these findings could suggest potential chemical risk factors and need further investigation.  相似文献   
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