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221.
The synthesis of a number of new benzothiopyrano[4,3,2-cd]isoindole aminoderivatives designed as structural analogues of the key metabolite of the anticancer agent Ledacrine (nitracrine) and their in vitro cytotoxic activity evaluation against HCT-116, MES-SA, and MES-SA/Dx cancer cell lines is reported. The majority of the derivatives possessed noticeable cytotoxicity in a low μM range indicating an interesting structure-activity relationship.  相似文献   
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Rapid and reliable laboratory diagnosis of persons suspected of Middle East respiratory syndrome coronavirus (MERS-CoV) infection is important for timely implementation of infection control practices and disease management. In addition, monitoring molecular changes in the virus can help elucidate chains of transmission and identify mutations that might influence virus transmission efficiency. This was illustrated by a recent laboratory investigation we conducted on an imported MERS-CoV case in Greece. Two oropharyngeal swab specimens were collected on the 1st and 2nd day of patient hospitalization and tested using two real-time RT-PCR (rRT-PCR) assays targeting the UpE and Orf-1a regions of the MERS-CoV genome and RT-PCR and partial sequencing of RNA-dependent RNA polymerase and nucleocapsid genes. Serum specimens were also collected and serological test were performed. Results from the first swab sample were inconclusive while the second swab was strongly positive for MERS-CoV RNA by rRT-PCR and confirmed positive by RT-PCR and partial gene sequencing. Positive serologic test results further confirmed MERS-CoV infection. Full-length nucleocapsid and spike gene coding sequences were later obtained from the positive swab sample. Phylogenetic analysis revealed that the virus was closely related to recent human-derived MERS-CoV strains obtained in Jeddah and Makkah, Saudi Arabia, in April 2014 and dromedary camels in Saudi Arabia and Qatar. These findings were consistent with the patient’s history. We also identified a unique amino acid substitution in the spike receptor binding domain that may have implications for receptor binding efficiency. Our initial inconclusive rRT-PCR results highlight the importance of collecting multiple specimens from suspect MERS-CoV cases and particularly specimens from the lower respiratory tract.  相似文献   
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This study investigated the temporal composition of an osteogenic extracellular matrix construct generated by culturing mesenchymal stem cells in an electrospun biodegradable poly(ε-caprolactone) fiber mesh scaffold within a flow perfusion bioreactor. Constructs of different extracellular matrix maturities were analyzed for their protein and mineral composition at several culture durations by liquid chromatography-tandem mass spectrometry, scanning electron microscopy, energy-dispersive X-ray diffraction, X-ray diffraction, and calcium and phosphate assays. The analysis revealed that at short culture durations the cells deposited cellular adhesion proteins as a prerequisite protein network for further bone formation. At the later culture durations, the extracellular matrix was composed of collagen 1, hydroxyapatite, matrix remodeling proteins, and regulatory proteins. These results suggest that the later culture duration constructs would allow for improved bone regeneration due to the ability to mineralize and the capabilities for future remodeling.  相似文献   
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AimsIntestinal ischemia/reperfusion (I/R) injury is implicated in many clinical conditions, and it performs a fundamental role in their pathophysiologies. Oral administration of antioxidants and nitric oxide (NO) donors ameliorate intestinal injury. Here, the effects of l-arginine, allopurinol and NG-nitro-l-arginine methyl ester (l-NAME) were investigated.Main methodsOne hundred twenty-eight male Wistar rats were separated into 4 groups and subjected to occlusion of the superior mesenteric artery for 60 min. The Control group did not receive any substance before the surgical operation. However, the 3 other groups received the following: l-arginine (800 mg/kg body weight; l-Arg group), l-NAME (50 mg/kg; l-NAME group) or allopurinol (100 mg/kg; Allo group). Each substance was given by mouth in 3 equal doses 24, 12 and 1 h before the surgical operation. Each group was then divided into 4 subgroups, which underwent different durations of reperfusion (0, 1, 8 or 24 h). At the end of each time point, blood and tissue samples were collected, and histological examinations were performed. Serum nitrite and catalase, intestinal tissue myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT) levels were determined.Key findingsAt each reperfusion time point, the Allo group exhibited the mildest histological lesions in contrast to the l-NAME group, which showed the most severe lesions. MPO was decreased significantly in the Allo and l-Arg groups during reperfusion, and allopurinol administration caused earlier and stronger effect. iNOS and NT levels were higher in the l-Arg group and lower in the Allo group. Serum nitrite and catalase were increased in the l-NAME group after 24 h.SignificanceOral administration of allopurinol exerted a strong and protective effect on the intestinal tissue that was subjected to I/R earlier than l-arginine. This finding was also supported with the MPO, iNOS and NT data.  相似文献   
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Laterality is a basic characteristic of the brain which is detectable early in life. Although early experiences affect laterality of the mature brain, there are no reports on their immediate neurochemical effects during neonatal life, which could provide evidence as to the mechanisms leading to the lateralized brain. In order to address this issue, we determined the differential protein expression profile of the left and right hippocampus of 13-day-old rat control (CTR) pups, as well as following exposure to an early experience involving either receipt (RER) or denial (DER) of the expected reward of maternal contact. Proteomic analysis was performed by 2-dimensional polyacrylamide gel electrophoresis (PAGE) followed by mass spectroscopy. The majority of proteins found to be differentially expressed either between the three experimental groups (DER, RER, CTR) or between the left and right hemisphere were cytoskeletal (34%), enzymes of energy metabolism (32%), and heat shock proteins (17%). In all three groups more proteins were up-regulated in the left compared to the right hippocampus. Tubulins were found to be most often up-regulated, always in the left hippocampus. The differential expression of β-tubulin, β-actin, dihydropyrimidinase like protein 1, glial fibrillary acidic protein (GFAP) and Heat Shock protein 70 revealed by the proteomic analysis was in general confirmed by Western blots. Exposure to the early experience affected brain asymmetry: In the RER pups the ratio of proteins up-regulated in the left hippocampus to those in the right was 1.8, while the respective ratio was 3.6 in the CTR and 3.4 in the DER. Our results could contribute to the elucidation of the cellular mechanisms mediating the effects of early experiences on the vulnerability for psychopathology, since proteins shown in our study to be differentially expressed (e.g. tubulins, dihydropyrimidinase like proteins, 14-3-3 protein, GFAP, ATP synthase, α-internexin) have also been identified in proteomic analyses of post-mortem brains from psychiatric patients.  相似文献   
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