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981.
982.
The first goal of this study was to obtain, Child Behavior Checklist (CBCL) and Youth Self-Report (YSR) problem-scales data for youths in Croatia, and compare them to the original American sample. The second goal of this study was to compare boys -girls problem scales data and CBCL-YSR differences. The instruments were administered to school adolescents aged between 12-18 comprising a non-referred sample (n=611) drawn from the whole country. Youths, compared to their parents, rated higher scores in all scales in both sexes (p < 0.001). According to parents' reports boys had higher scores in more scales (five out of eleven). According to adolescents'self-reports girls had higher scores in more scales (seven out of eleven). Consistent with other studies, Croatian sample confirmed a larger number of serious behavioral and emotional problems reported by adolescents. Adolescents were confirmed as the most reliable informants on their problems. 相似文献
983.
Opletal L Sovová H Bártlová M 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,812(1-2):357-371
The drug Wuweizi (dried fruits of Schisandra chinensis or S. sphenantherd) is one of important medicinal means used in the Oriental medicine. The lignans of dibenzo[a,c]cyklooctadiene type are major constituents, a volatile oil with mono- and ses-quiterpens, an oil, organic acids and small amounts of additional compounds are also present. The content of major lignans (schizandrin, deoxyschizandrin, gomisin A, gomisin N, gamma-schizandrin, wuweizisu C) in commercially available drugs ranges usually between 3 and 5%. The present paper biefly comments the isolation and biological activity of the lignans and is especially concerned with analytical methods (TLC and HPLC) for the determination of the drug fingerprint and methods for the determination of constituents in drugs, mixtures and biological materials. HPLC methods using RP-silica bonded phases and diluted methanol, acetonitrile (or a mixture of both), are most important for these purposes. Electromigration methods are less suitable and the importance of hyphenation procedures is practically negligible. 相似文献
984.
Plasma membrane oxidoreductase activity in cultured cells in relation to mitochondrial function and oxidative stress 总被引:2,自引:0,他引:2
Deleonardi G Biondi A D'Aurelio M Pich MM Stankov K Falasca A Formiggini G Bovina C Romeo G Lenaz G 《BioFactors (Oxford, England)》2004,20(4):251-258
Dichlorophenol indophenol (DCIP) reduction by intracellualr pyridine nucleotides was investigated in two different lines of cultured cells characterized by enhanced production of reacive oxygen species (ROS) with respect to suitable controls. The first line denominated XTC-UC1 was derived from a metastasis of an oxyphilic thyroid tumor characterized by mitochondrial hyperplasia and compared with a line (B-CPAP) derived from a papillary thyroid carcinoma with normal mitochondrial mass. The second line (170 MN) was a cybrid line derived from rho0 cells from an osteosarcoma line (143B) fused with platelets from a patient with a nucleotide 9957 mutation in mitochondrial DNA (encoding for cytochrome c oxidase subunit III) in comparison with the parent 143B line. The experimental lines had no major decreases of electron transfer activities with respect to the controls; both of them, however, exhibited an increased peroxide production. The XTC-UC1 cell line exhibited enhanced activity with respect to control of dicoumarol-sensitive DCIP reduction, identified with membrane bound DT-diaphorase, whereas dicoumarol insensitive DCIP reduction was not significantly changed. On the other hand the mtDNA mutated cybrids exhibited a strong increase of both dicoumarol sensitive and insensitive DCIP reduction. The results suggest that enhanced oxidative stress and not deficient respiratory activity per se is the stimulus triggering over-expression of plasma membrane oxidative enzymes. 相似文献
985.
Overexpression of the rice Osmyb4 gene increases chilling and freezing tolerance of Arabidopsis thaliana plants 总被引:11,自引:0,他引:11
Vannini C Locatelli F Bracale M Magnani E Marsoni M Osnato M Mattana M Baldoni E Coraggio I 《The Plant journal : for cell and molecular biology》2004,37(1):115-127
The expression of the gene Osmyb4, detected at low level in rice (Oryza sativa) coleoptiles grown for 3 days at 29 degrees C, is strongly induced by treatments at 4 degrees C. At sublethal temperatures of 10 and 15 degrees C, its expression in rice seedlings is already evident, but this effect cannot be vicariated by other stresses or ABA treatment. We demonstrate by transient expression that Myb4 transactivates the PAL2, ScD9 SAD and COR15a cold-inducible promoters. The Osmyb4 function in vivo is demonstrated overexpressing its cDNA in Arabidopsis thaliana plants (ecotype Wassilewskija) under the control of the constitutive CaMV 35S promoter. Myb4 overexpressing plants show a significant increased cold and freezing tolerance, measured as membrane or Photosystem II (PSII) stability and as whole plant tolerance. Finally, in Osmyb4 transgenic plants, the expression of genes participating in different cold-induced pathways is affected, suggesting that Myb4 represents a master switch in cold tolerance. 相似文献
986.
Synthesis and antiproliferative activity of 2,6-diamino-9-benzyl-9-deazapurine and related compounds
Treatment of 6-bromomethyl- or 6-dibromomethyl-5-nitropyrimidine-2,4-diamine with KCN gave the same product--(2,6-diamino-5-nitropyrimidinyl)acetonitrile. Benzylation of the nitrile took place on the alpha-carbon to the cyano group preferentially affording the corresponding mono- and dibenzyl derivative, whose reductive cyclization resulted in 7-benzyl-5H-pyrrolo[3,2-d]pyrimidine-2,4-diamine and 7,7-dibenzyl-7H-pyrrolo[3,2-d]pyrimidine-2,4,6-triamine, respectively. Suitability of the protection of N(2) and N(4) atoms with benzyl, acetyl, or benzoyl groups was also investigated. The in vitro evaluation of cell growth inhibition on CCRF-CEM, HL-60, HeLa S3, and L1210 cell lines showed significant activity in 8 new compounds. The most potent compounds were the above mentioned 6-dibromomethyl derivative (IC(50)=0.54, 1.7, 5.0, and 1.9 molL(-1)) and 7,N(2),N(4)-tribenzyl-5H-pyrrolo[3,2-d]pyrimidine-2,4-diamine (IC(50)=1.9, 2.7, 7.3, and 1.0 molL(-1)). 相似文献
987.
Hocková D Holý A Masojídková M Andrei G Snoeck R De Clercq E Balzarini J 《Bioorganic & medicinal chemistry》2004,12(12):3197-3202
Synthesis of 2,4-diamino-5-cyano-6-[[(diisopropoxyphosphoryl)methoxy]ethoxy]pyrimidine was based on the formation of the pyrimidine ring by cyclization followed by modification of the side chain by alkylation. The 5-cyano group was also transformed to a 5-formyl and 5-hydroxymethyl group by reduction. As a side product an unexpected dimer was formed. Resulting compounds were converted to the free phosphonic acids by treatment with bromotrimethylsilane followed by hydrolysis. The 5-cyano and 5-formyl derivatives showed pronounced antiretroviral activity, comparable to that of the reference drugs adefovir and tenofovir. 相似文献
988.
The mannitol transporter EII(mtl) from Escherichia coli is responsible for the uptake of mannitol over the inner membrane and its concomitant phosphorylation. EII(mtl) is functional as a dimer and its membrane-embedded C domain, IIC(mtl), harbors one high affinity mannitol binding site. To characterize this domain in more detail the microenvironments of thirteen residue positions were explored by 5-fluorotryptophan (5-FTrp) fluorescence spectroscopy. Because of the simpler photophysics of 5-FTrp compared to Trp, one can distinguish between the two 5-FTrp probes present in dimeric IIC(mtl). At many labeled positions, the microenvironment of the 5-FTrps in the two protomers differs. Spectroscopic properties of three mutants labeled at positions 198, 251, and 260 show that two conserved motifs (Asn194-His195 and Gly254-Ile255-His256-Glu257) are located in well-structured parts of IIC(mtl). Mannitol binding has a large impact on the structure around position 198, while only minor changes are induced at positions 251 and 260. Phosphorylation of the cytoplasmic B domain of EII(mtl) is sensed by 5-FTrp at positions 30, 42, 251 and 260. We conclude that many parts of the IIC(mtl) structure are involved in the sugar translocation. The structure of EII(mtl), as investigated in this work, differs from the recently solved structure of a IIC protein transporting diacetylchitobiose, ChbC, and also belonging to the glucose superfamily of EII sugar transporters. In EII(mtl), the sugar binding site is more close to the periplasmic face and the structure of the 2 protomers in the dimer is different, while both protomers in the ChbC dimer are essentially the same. 相似文献
989.
Abigail Manson McGuire Brian Weiner Sang Tae Park Ilan Wapinski Sahadevan Raman Gregory Dolganov Matthew Peterson Robert Riley Jeremy Zucker Thomas Abeel Jared White Peter Sisk Christian Stolte Mike Koehrsen Robert T Yamamoto Milena Iacobelli-Martinez Matthew J Kidd Andreia M Maer Gary K Schoolnik Aviv Regev James Galagan 《BMC genomics》2012,13(1):1-27
Background
The sequence of the pathogen Mycobacterium tuberculosis (Mtb) strain H37Rv has been available for over a decade, but the biology of the pathogen remains poorly understood. Genome sequences from other Mtb strains and closely related bacteria present an opportunity to apply the power of comparative genomics to understand the evolution of Mtb pathogenesis. We conducted a comparative analysis using 31 genomes from the Tuberculosis Database (TBDB.org), including 8 strains of Mtb and M. bovis, 11 additional Mycobacteria, 4 Corynebacteria, 2 Streptomyces, Rhodococcus jostii RHA1, Nocardia farcinia, Acidothermus cellulolyticus, Rhodobacter sphaeroides, Propionibacterium acnes, and Bifidobacterium longum.Results
Our results highlight the functional importance of lipid metabolism and its regulation, and reveal variation between the evolutionary profiles of genes implicated in saturated and unsaturated fatty acid metabolism. It also suggests that DNA repair and molybdopterin cofactors are important in pathogenic Mycobacteria. By analyzing sequence conservation and gene expression data, we identify nearly 400 conserved noncoding regions. These include 37 predicted promoter regulatory motifs, of which 14 correspond to previously validated motifs, as well as 50 potential noncoding RNAs, of which we experimentally confirm the expression of four.Conclusions
Our analysis of protein evolution highlights gene families that are associated with the adaptation of environmental Mycobacteria to obligate pathogenesis. These families include fatty acid metabolism, DNA repair, and molybdopterin biosynthesis. Our analysis reinforces recent findings suggesting that small noncoding RNAs are more common in Mycobacteria than previously expected. Our data provide a foundation for understanding the genome and biology of Mtb in a comparative context, and are available online and through TBDB.org. 相似文献990.
Marotta V Nuzzo V Ferrara T Zuccoli A Masone M Nocerino L Del Prete M Marciello F Ramundo V Lombardi G Vitale M Colao A Faggiano A 《Biomarkers》2012,17(2):186-191
Context: Usefulness of circulating Chromogranin A (CgA) for the diagnosis of neuroendocrine tumors (NEN) is controversial. The aim of the present study was to assess the actual role of this marker as diagnostic tool. Methods: Serum blood samples were obtained from 42 subjects affected with NEN, 120 subjects affected with non-endocrine neoplasias (non-NEN) and 100 non-neoplastic subjects affected with benign nodular goitre (NNG). Determination of CgA was performed by means of immunoradiometric assay. Results: The CgA levels among NEN-patients were not significantly different from NNG and non-NEN subjects. The Receiver operating characteristic (ROC) curves analysis failed to identify a feasible cut-off value for the differential diagnosis between NEN and the other conditions. Conclusion: Serum CgA is not helpful for the first-line diagnosis of NEN. 相似文献