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961.
962.
Equine herpesvirus 1 (EHV-1), like other members of the Alphaherpesvirinae subfamily, is a neurotropic virus causing latent infections in the nervous system of the natural host. In the present study, we have investigated EHV-1 replication (wild-type Jan-E strain and Rac-H laboratory strain) during long-term infection and during the passages of the virus in cultured neurons. The studies were performed on primary murine neurons, which are an excellent in vitro model for studying neurotropism and neurovirulence of EHV-1. Using real-time cell growth analysis, we have demonstrated for the first time that primary murine neurons are able to survive long-term EHV-1 infection. Positive results of real-time PCR test indicated a high level of virus DNA in cultured neurons, and during long-term infection, these neurons were still able to transmit the virus to the other cells. We also compared the neurovirulence of Rac-H and Jan-E EHV-1 strains after multiple passages of these strains in neuron cell culture. The results showed that multiple passages of EHV-1 in neurons lead to the inhibition of viral replication as early as in the third passage. Interestingly, the inhibition of the EHV-1 replication occurred exclusively in neurons, because the equine dermal (ED) cells co-cultivated with neuroculture medium from the third passage showed the presence of large amount of viral DNA. In conclusion, our results showed that certain balance between EHV-1 and neurons has been established during in vitro infection allowing neurons to survive long-term infection.  相似文献   
963.
The aim of the study was to describe the morphology of the upper, lower and third eyelid and characterize the organized lymphoid follicles and diffuse lymphocytes from ornamental and wild birds. The goal of these examinations was also to identify avian conjunctiva‐associated lymphoid tissue (CALT) and lymphoid tissue that contained specialized high endothelial venules. The upper, lower and third eyelid from 30 species of ornamental and wild birds representing 21 families were examined under light microscopy and using scanning electron microscopy. The third eyelid in all of the examined birds was composed of a free margin, which was divided into two parts. The largest tarsal plate of the third eyelid was observed in the greater rhea (Rheimorphae), the white‐tailed eagle and steppe eagle (Accipitrimorphae) and was approximately 13–15 mm wide and 9–11 mm long, respectively. In all of the examined birds, the CALT was associated with a rich network of small vessels. In addition, the presence of characteristic high endothelial venules and roundish bright endothelial cells was confirmed in the upper and lower eyelids or only in the lower eyelid (Phoenicopterimorphae, Procellariimorphae and Strigimorphae).  相似文献   
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965.
Molecular Biology Reports - Coumarin is a plant-derived compound but as such has no medical uses. Several synthetic coumarin analogs have been shown to possess anti-proliferative activity and to...  相似文献   
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968.
We report synthesis of silver nanoparticles (AgNPs) from Streptomyces xinghaiensis OF1 strain, which were characterised by UV–Vis and Fourier transform infrared spectroscopy, Zeta sizer, Nano tracking analyser, and Transmission electron microscopy. The antimicrobial activity of AgNPs alone, and in combination with antibiotics was evaluated against bacteria, namely Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis, and yeasts viz., Candida albicans and Malassezia furfur by using micro-dilution method. The minimum inhibitory concentration (MIC) and minimum biocidal concentration of AgNPs against bacterial and yeast strains were determined. Synergistic effect of AgNPs in combination with antibacterial and antifungal antibiotics was determined by FIC index. In addition, MTT assay was performed to study cytotoxicity of AgNPs alone and in combination with antibiotics against mouse fibroblasts and HeLa cell line. Biogenic AgNPs were stable, spherical, small, polydispersed and capped with organic compounds. The variable antimicrobial activity of AgNPs was observed against tested bacteria and yeasts. The lowest MIC (16 µg ml?1) of AgNPs was found against P. aeruginosa, followed by C. albicans and M. furfur (both 32 µg ml?1), B. subtilis and E. coli (both 64 µg ml?1), and then S. aureus and Klebsiella pneumoniae (256 µg ml?1). The high synergistic effect of antibiotics in combination with AgNPs against tested strains was found. The in vitro cytotoxicity of AgNPs against mouse fibroblasts and cancer HeLa cell lines revealed a dose dependent potential. The IC50 value of AgNPs was found in concentrations of 4 and 3.8 µg ml?1, respectively. Combination of AgNPs and antibiotics significantly decreased concentrations of both antimicrobials used and retained their high antibacterial and antifungal activity. The synthesis of AgNPs using S. xinghaiensis OF1 strain is an eco-friendly, cheap and nontoxic method. The antimicrobial activity of AgNPs could result from their small size. Remarkable synergistic effect of antibiotics and AgNPs offer their valuable potential in nanomedicine for clinical application as a combined therapy in the future.  相似文献   
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970.
A series of optically pure (R)- and (S)-1,3,4,12a-tetrahydropyrazino[2,1-c][1,4]benzodiazepine-6,12(2H,11H)-dione derivatives was designed and synthesized as novel anthramycin analogues in a three-step, one-pot procedure, and tested for their antiproliferative activity on nine following cell lines: MV-4-11, UMUC-3, MDA-MB-231, MCF7, LoVo, HT-29, A-549, A2780 and BALB/3T3. The key structural features responsible for exhibition of cytotoxic effect were determined: the (S)-configuration of chiral center and the presence of hydrophobic 4-biphenyl substituent in the side chain. Introduction of bromine atom into the 8 position (8g) or substitution of dilactam ring with benzyl group (8m) further improved the activity and selectivity of investigated compounds. Among others, compound 8g exhibited selective cytotoxic effect against MV-4-11 (IC50?=?8.7?μM) and HT-29 (IC50?=?17.8?μM) cell lines, while 8m showed noticeable anticancer activity against MV-4-11 (IC50?=?10.8?μM) and LoVo (IC50?=?11.0?μM) cell lines. The cell cycle arrest in G1/S checkpoint and apoptosis associated with overproduction of reactive oxygen species was also observed for 8e and 8m.  相似文献   
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