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91.
Metal and metal oxide nanoparticles are being used in different industries now‐a‐days leading to their unavoidable exposure to humans and animals. In the present study, toxicological testing was done using nanoparticles of copper oxide, cerium oxide and their mixture (1:1 ratio) on zebra fish embryos and THP‐1 cell line. Zebrafish embryos were exposed to 0.01 μg/ml to 50 μg/ml concentrations of dispersed nanoparticles using a 96 well plate and their effects were studied at different hours post fertilization (hpf) i.e. 0 hpf, 24 hpf, 48 hpf, 72 hpf and 96 hpf respectively. Results showed that copper oxide nanoparticles has drastic effects on the morphology and physiology of zebra fish whereas cerium oxide nanoparticles and mixture of these nanoparticles did not show much of the effects. Comparable results were obtained from in vitro study using human monocyte cell line (THP‐1). It is concluded that these nanoparticles may cause toxicological effects to humans and environment.  相似文献   
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Immunologic Research - A powerful interaction between the autonomic and the immune systems plays a prominent role in the initiation and maintenance of hypertension and significantly contributes to...  相似文献   
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The aim of the present study was to evaluate in vivo modulatory effect of S-methylisothiourea (SMT), a preferential inhibitor of inducible nitric oxide synthase (iNOS) on pain and pathology in the surgical model of osteoarthritis (OA) in rats. The OA was produced by the anterior cruciate ligament transection (ACLT) and medial meniscectomy (MMx) of right knee. SMT was administered 1 day prior to the production of OA and continued up to day 42 postoperation. Mechanical hyperalgesia, thermal hyperalgesia, tail flick latency after repeated flexion and extension of OA knee and knee diameter of right knee were determined at weekly intervals. Serum levels of IL-1β, TNF-α and nitrite concentration were determined at the end of the experiment. Glycosaminoglycan (GAG) content, collagen content and histopathological evaluation of articular cartilage were also determined at the end of the experiment. SMT reduced mechanical hyperalgesia and the serum levels of IL-1β, TNF-α and nitrite. Further, SMT reduced the loss of GAG from articular cartilage. Microscopically, SMT reduced the severity of the cartilage lesion. The results indicate the effectiveness of SMT in attenuating the pain and pathology of experimental OA phase by reducing the production of nitric oxide and interleukin-1β and tumor necrosis factor-α, which are known to play a major role in the pathophysiology of OA.  相似文献   
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Journal of Molecular Neuroscience - Reports of spectrum of clinical manifestations in PMP22 gene–associated neuropathies (duplication/mutations) are scarce. To identify the frequency of PMP22...  相似文献   
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Background

The Variation in Revascularization Practice in Ontario (VRPO) project helped describe variations in revascularization across Ontario. Coronary anatomy was the most important predictor of revascularization strategy. We conducted a novel angiographic substudy of the VRPO cohort to: (1) validate “real-world” coronary angiographic reporting in the province of Ontario; and (2) understand the relationship between variability in revascularization and coronary anatomy complexity.

Methods

Seventeen hundred eighty-seven angiograms from 17 cardiac centres were randomly sampled from the VRPO cohort. The core lab assessment involved blinded interpretation of each angiographic film. A comparison of agreement in coronary anatomy and treatment strategy between abstracted chart data from the VRPO study and blinded film review was undertaken. Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) scores were calculated for all patients with multivessel disease.

Results

The weighted κ statistic for coronary anatomy was 0.75 (95% confidence interval, 0.72-0.77), suggesting substantial agreement between abstracted chart data and blinded film review. The weighted κ for revascularization strategy was 0.51 (95% confidence interval, 0.47-0.54) suggesting only moderate agreement. There were no significant differences in the mean/median SYNTAX scores across all 4 percutaneous coronary intervention: coronary artery bypass graft (CABG) groups.

Conclusions

Abstracted chart data in the VRPO project provides a valid assessment of coronary anatomy and furthermore serves as validation of “real-world” coronary angiographic reporting in the province of Ontario. The uniform distribution of coronary complexity across centres in Ontario, with respect to the SYNTAX score, suggests the variation of percutaneous coronary intervention: CABG ratio is not related to a difference in coronary anatomy complexity across sites, but rather a difference in management strategies for the same anatomy.  相似文献   
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Citrus tristeza virus (CTV) populations are among the more complex of plant RNA viruses with unusual mixtures of strains and defective RNAs (dRNAs). Citrus plants infected with different CTV isolates contain multiple dRNA molecules that differ in size and relative abundance within and between isolates. Additionally, we found mixtures of heterologous dRNAs in populations. To examine the replication of CTV dRNAs, the protoplast system had to be extended to support helper-assisted amplification of input dRNAs. The use of freshly extracted sap of CTV-infected tissue as inoculum increased the infection of Nicotiana benthamiana protoplasts sufficiently to result in accumulation of high levels of CTV RNAs as well as dRNAs within 2 or 3 days postinoculation. A series of dRNA-like molecules, each with a single large internal deletion, were created from an infectious cDNA clone of the CTV T36 isolate and examined for amplification in N. benthamiana protoplasts using a CTV deletion mutant as the helper virus. Of 12 synthetic dRNAs, only three with sizes of 3650, 3819, and 4460 nucleotides were efficiently replicated. CTV dRNA replication did not appreciably affect levels of accumulation of the genomic or the subgenomic RNAs of the helper virus. To investigate the maintenance of dRNAs in CTV populations, we examined heterologous interactions between dRNAs and helper viruses. Wild-type populations of heterologous strains T68 and T3, as well as the homologous T36, supported replication of synthetic T36 dRNAs. Replacement in the T36 dRNA of the 5' region, which is most variable among CTV strains, with the corresponding sequences from VT, T68, T3, or T30 resulted in chimeric dRNAs that failed to be replicated by the T36 helpers but were replicated to detectable levels by the T68 helper. The differential specificities of different CTV replicase complexes with dRNA replication signals is one possible factor that affects the maintenance of dRNA population structures.  相似文献   
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