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211.
Age-related changes in haematology and serum chemistry of Weiser-Maples guineapigs (Cavia porcellus)
Age-related changes in haematology and serum chemistry values were examined in male and female Weiser-Maples guineapigs (Cavia porcellus). Haematological changes that significantly (P<0.01) correlated with ageing were increased white blood cell and neutrophil counts in both sexes, decreased lymphocyte counts in both sexes, decreased reticulocyte and platelet counts in males, and decreased basophil counts in females. For serum chemistry, increases in total protein, triglycerides, blood urea nitrogen and creatinine were seen in both sexes, along with increases in total cholesterol in males and sodium in females. Decreased alkaline phosphatase in both sexes and decreased chloride in males were significantly (P<0.01) associated with age. These age-related changes are compared with the published literature. 相似文献
212.
Nakamura M Fukunaga Y Sasa K Ohtoshi Y Kanaori K Hayashi H Nakano H Yamana K 《Nucleic acids research》2005,33(18):5887-5895
Through binding and fluorescence studies of oligonucleotides covalently attached to a pyrene group via one carbon linker at the sugar residue, we previously found that pyrene-modified RNA oligonucleotides do not emit well in the single-stranded form, yet the attached pyrene emits with a significantly high quantum yield upon binding to a complementary RNA strand. In sharp contrast, similarly modified pyrene–DNA probes exhibit very weak fluorescence both in the double-stranded and single-stranded forms. The pyrene-modified RNA oligonucleotides therefore provide a useful tool for monitoring RNA hybridization. The purpose of this paper is to present the structural basis for the different fluorescence properties of pyrene-modified RNA/RNA and pyrene-modified DNA/DNA duplexes. The results of absorption, fluorescence anisotropy and circular dichroism studies all consistently indicated that the pyrene attached to the RNA duplex is located outside of the duplex, whereas the pyrene incorporated into the DNA duplex intercalates into the double helix. 1H NMR measurements unambiguously confirmed that the pyrene attached to the DNA duplex indeed intercalates between the base pairs of the duplex. Molecular dynamics simulations support these differences in the local structural elements around the pyrene between the pyrene–RNA/RNA and the pyrene–DNA/DNA duplexes. 相似文献
213.
Endothelial lipase is inactivated upon cleavage by the members of the proprotein convertase family 总被引:2,自引:0,他引:2
Mature endothelial lipase (EL) is a 68 kDa glycoprotein. In HepG2 cells infected with adenovirus encoding human EL, the mature EL was detectable in the cell lysates and heparin-releasable fractions. In contrast, cell media of these cells contained two EL fragments: an N-terminal 40 kDa fragment and a C-terminal 28 kDa fragment. N-terminal protein sequencing of the His-tagged 28 kDa fragment revealed that EL is cleaved on the C terminus of the sequence RNKR330, the consensus cleavage sequence for mammalian proprotein convertases (pPCs). Replacement of Arg-330 with Ser by site-directed mutagenesis totally abolished EL processing. EL processing could efficiently be attenuated by specific inhibitors of pPCs, alpha1-antitrypsin Portland (alpha1-PDX) and alpha1-antitrypsin variant AVRR. Coexpression of the pPCs furin, PC6A, and PACE4 with EL resulted in a complete conversion of the full-length EL to a truncated 40 kDa fragment. Exogenously added EL was also processed by cells, and the processing could be attenuated by alpha1-PDX. The expressed N-terminal 40 kDa fragment of EL (EL-40) harboring the catalytic site failed to hydrolyze [14C]NEFA from [14C]dipalmitoyl-PC-labeled HDL. EL-40 was incapable of bridging 125I-labeled HDL to the cells and had no impact on plasma lipid concentration when overexpressed in mice. Thus, our results demonstrate that pPCs are involved in the inactivation process of EL. 相似文献
214.
Sanbongi C Takano H Osakabe N Sasa N Natsume M Yanagisawa R Inoue K Kato Y Osawa T Yoshikawa T 《Free radical biology & medicine》2003,34(8):1060-1069
Epidemiological and experimental studies have suggested that diesel exhaust particles (DEP) may be involved in recent increases in lung diseases. DEP has been shown to generate reactive oxygen species. Intratracheal instillation of DEP induces lung inflammation and edema in mice. Rosmarinic acid is a naturally occurring polyphenol with antioxidative and anti-inflammatory activities. We investigated the effects of rosmarinic acid on lung injury induced by intratracheal administration of DEP (500 microg/body) in mice. Oral supplementation with administration of rosmarinic acid (2 mg/body for 3 d) inhibited DEP-induced lung injury, which was characterized by neutrophil sequestration and interstitial edema. DEP enhanced the lung expression of keratinocyte chemoattractant (KC), interleukin-1beta, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1alpha, which was inhibited by treatment with rosmarinic acid. DEP enhanced expression of iNOS mRNA and formation of nitrotyrosine and 8-OHdG in the lung, which was also inhibited by rosmarinic acid. These results suggest that rosmarinic acid inhibits DEP-induced lung injury by the reduction of proinflammatory molecule expression. Antioxidative activities of rosmarinic acid may also contribute to its protective effects. 相似文献
215.
Popsavin M Torović L Kojić V Bogdanović G Spaić S Popsavin V 《Bioorganic & medicinal chemistry letters》2003,13(19):3167-3170
A divergent synthesis of two novel tiazofurin analogues, 2-(3-deoxy-3-fluoro-beta-D-xylofuranosyl)thiazole-4-carboxamide (2) and 2-(3-acetamido-3-deoxy-beta-D-xylofuranosyl)thiazole-4-carboxamide (3), has been achieved starting from D-glucose. Both nucleoside analogues were evaluated for their in vitro cytotoxicity against several human leukaemia and solid tumour cell lines. 相似文献
216.
217.
Lakota K Thallinger GG Sodin-Semrl S Rozman B Ambrozic A Tomsic M Praprotnik S Cucnik S Mrak-Poljsak K Ceribelli A Cavazzana I Franceschini F Vencovsky J Czirják L Varjú C Steiner G Aringer M Stamenkovic B Distler O Matucci-Cerinic M Kveder T 《Arthritis research & therapy》2012,14(1):R2-8
Introduction
An international cohort study of 73 anti-Ku-positive patients with different connective tissue diseases was conducted to differentiate the anti-Ku-positive populations of patients based on their autoantibody profile and clinical signs/symptoms and to establish possible correlations between antibodies against Ku p70 and Ku p80 with autoimmune diseases.Methods
Sera of anti-Ku-positive patients were collected from six European centers and were all secondarily tested (in the reference center); 73 were confirmed as positive. Anti-Ku antibodies were detected with counter-immunoelectrophoresis (CIE), line immunoassay (LIA), and immunoblot analyses. All clinical and laboratory data were follow-up cumulative data, except for anti-Ku antibodies. Statistical analyses were performed by using R (V 2.12.1). The Fisher Exact test was used to evaluate the association between anti-Ku antibodies and diagnosis, gender, clinical signs, and other observed antibodies. The P values were adjusted for multiple testing. Separation of disease populations based on the presence of antibodies and clinical signs was investigated by principal-components analysis, which was performed by using thr// R's prcomp function with standard parameters.Results
A 16% higher prevalence of anti-Ku p70 was found over anti-Ku p80 antibodies. In 41 (57%) patients, a combination of both was detected. Five (7%) patients, who were CIE and/or LIA anti-Ku positive, were negative for both subsets, as detected with the immunoblot; 31% of the patients had undifferentiated connective tissue disease (UCTD); 29% had systemic sclerosis (SSc); 18% had systemic lupus erythematosus (SLE); 11% had rheumatoid arthritis; 7% had polymyositis; and 3% had Sjögren syndrome.Conclusions
A significant positive association was found between female patients with anti-Ku p70 and joint/bone features, and a significant negative association was found between female patients with anti-Ku p80 only and joint/bone features (P = 0.05, respectively). By using the first and the third components of the principal-component analysis (PCA) with 29 parameters evaluated, we observed that the anti-Ku-positive population of UCTD patients had overlapping parameters, especially with SLE, as opposed to SSc, which could be helpful in delineating UCTD patients. 相似文献218.
219.
Missoni S 《Collegium antropologicum》2006,30(3):673-696
This paper is dedicated to the pioneers of nutritional research in Croatia: to Professor Edvin Ferber, Professor Hubert Maver and Professor Ratko Buzina, to whom we owe exceptional contribution in the development of science of nutrition, as well as for many scientific publications from the fifties to the eighties in the 20th century, leaving us great information about nutritional state in Croatian population. The paper brings a review of nuitritional research in Croatia with an emphasis on history of research and papers published in Collegium Antropologicum. Since first publications on the subject, a number of institutions and scholars participated in numerous research projects which resulted in a vast number of published papers, depicting a multidisciplinary approach to the subject. In addition, the results of 44 analyses that have been a part of doctoral (18) and master's research (26) are discussed. 相似文献
220.
Growth of regenerated tree seedlings associated with microclimatic change in a mature larch plantation after harvesting 总被引:1,自引:0,他引:1
Satoshi Kitaoka M. Watanabe Y. Watanabe M. Kayama M. Nomura K. Sasa 《Landscape and Ecological Engineering》2009,5(2):137-145
In order to further develop methods of sustainable forest management, we evaluated the effects of logging practices during
the winter on microclimatic factors and growth of four seral deciduous broad-leaved tree seedlings regenerated in a larch
plantation in northern Japan. We found that winter logging practices drastically changed microclimatic factors, especially
in terms of light intensity and the vertical distribution pattern of CO2 concentration. Harvesting overstory larch trees increased photosynthetic photon flux (PPF), which may enhance the photosynthesis
of understory plants. We examined the undergrowth for tree seedlings of the following species: two late successional species,
Prunus ssiori and Carpinus cordata; one gap phase species, Magnolia hyporeuca; and one mid-late successional species, Quercus mongolica var. crispula. All of the four studied tree species responded well to the practices of winter logging after the second year of harvesting
overstoried larch trees. The current shoot diameter and current shoot length increased significantly. Therefore, we conclude
that winter logging practices should improve shoot growth of deciduous broad-leaved tree seedlings regenerated in a larch
plantation through the change in environmental factors that accompanies larch harvest. 相似文献