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61.
Parasternal intercostal muscle remodeling in severe chronic obstructive pulmonary disease. 总被引:1,自引:0,他引:1
Sanford Levine Taitan Nguyen Michael Friscia Jianliang Zhu Wilson Szeto John C Kucharczuk Boris A Tikunov Neal A Rubinstein Larry R Kaiser Joseph B Shrager 《Journal of applied physiology》2006,101(5):1297-1302
Studies in experimental animals indicate that chronic increases in neural drive to limb muscles elicit a fast-to-slow transformation of fiber-type proportions and myofibrillar proteins. Since neural drive to the parasternal intercostal muscles (parasternals) is chronically increased in patients with severe chronic obstructive pulmonary diseases (COPDs), we carried out the present study to test the hypothesis that the parasternals of COPD patients exhibit an increase in the proportions of both slow fibers and slow myosin heavy chains (MHCs). Accordingly, we obtained full thickness parasternal muscle biopsies from the third interspace of seven COPD patients (mean +/- SE age: 59 +/- 4 yr) and seven age-matched controls (AMCs). Fiber typing was done by immunohistochemistry, and MHC proportions were determined by SDS-PAGE followed by densitometry. COPD patients exhibited higher proportions of slow fibers than AMCs (73 +/- 4 vs. 51 +/- 3%; P < 0.01). Additionally, COPD patients exhibited higher proportions of slow MHC than AMCs (56 +/- 4 vs. 46 +/- 4%, P < 0.04). We conclude that the parasternal muscles of patients with severe COPD exhibit a fast-to-slow transformation in both fiber-type and MHC proportions. Previous workers have demonstrated that remodeling of the external intercostals, another rib cage inspiratory muscle, elicited by severe COPD is characterized by a slow-to-fast transformation in both fiber types and MHC isoform proportions. The physiological significance of this difference in remodeling between these two inspiratory rib cage muscles remains to be elucidated. 相似文献
62.
B Alexandre F Thiébaut M Allary E Boschetti C Séné J Saint-Blancard 《Revue fran?aise de transfusion et immuno-hématologie》1987,30(1):57-66
In this work the human plasma fibronectin was purified by affinity chromatography using a tandem column system. The first affinity column was filled with gelatin-Trisacryl whereas the second one contained heparin-Trisacryl. This double affinity chromatography demonstrated its high efficiency in term of purity and yield. Several analytical methods (electrophoresis, immunoelectrophoresis, F.P.L.C. and adhesion assay on cultured eucaryotic cells) evidenced in fact the high purity of the preparation as well as its biological behaviour in term of cell adhesion and spreading. The performances of the sorbents used facilitate the scaling up when large quantities of FNP are needed. 相似文献
63.
G Thiéry M Bergeron 《Revue canadienne de biologie / éditée par l'Université de Montréal》1976,35(4):211-216
A new histological technique of block staining based on the use of a double lead and copper citrate is described in order to observe thick sections (0.5-1.5 micron) with a transmission electron microscope. With this technique, a network of mitochondrial with many morphological communications was seen in the epithelial cells of the proximal and distal convoluted tubules of the rat nephron. A new schematic view of the proximal and distal tubular cell is presented to illustrate the communications of the chondriome, which could become more or less accentuated following the functional status of the cell. 相似文献
64.
Giang Ngan Khong Nhu Thi Le Mai Thi Pham Helene Adam Carole Gauron Hoa Quang Le Dung Tien Pham Kelly Colonges Xuan Hoi Pham Vinh Nang Do Michel Lebrun Stefan Jouannic 《PLoS genetics》2021,17(6)
The number of grains per panicle is an important yield-related trait in cereals which depends in part on panicle branching complexity. One component of this complexity is the number of secondary branches per panicle. Previously, a GWAS site associated with secondary branch and spikelet numbers per panicle in rice was identified. Here we combined gene capture, bi-parental genetic population analysis, expression profiling and transgenic approaches in order to investigate the functional significance of a cluster of 6 ANK and ANK-TPR genes within the QTL. Four of the ANK and ANK-TPR genes present a differential expression associated with panicle secondary branch number in contrasted accessions. These differential expression patterns correlate in the different alleles of these genes with specific deletions of potential cis-regulatory sequences in their promoters. Two of these genes were confirmed through functional analysis as playing a role in the control of panicle architecture. Our findings indicate that secondary branching diversity in the rice panicle is governed in part by differentially expressed genes within this cluster encoding ANK and ANK-TPR domain proteins that may act as positive or negative regulators of panicle meristem’s identity transition from indeterminate to determinate state. 相似文献
65.
G Dumoulin N U Nguyen M T Henriet J Bopp S Berthelay 《Comptes rendus des séances de la Société de biologie et de ses filiales》1980,174(2):146-150
Plasma Na, K, Cl, Ca, P didn't or moderately be altered by exposure to acute heat in sauna bath (20 mn, 80 degrees C, relative humidity 15-20%). However, CO2T decreased, ARP, aldosterone, ACTH, PRL increased, and PTH wasn't modified. 相似文献
66.
Suppressive Subtractive Hybridization of and Differences in Gene Expression Content of Calcifying and Noncalcifying Cultures of Emiliania huxleyi Strain 1516 下载免费PDF全文
Binh Nguyen Robert M. Bowers Thomas M. Wahlund Betsy A. Read 《Applied microbiology》2005,71(5):2564-2575
The marine coccolithophorid Emiliania huxleyi is a cosmopolitan alga intensely studied in relation to global carbon cycling, biogeochemistry, marine ecology, and biomineralization processes. The biomineralization capabilities of coccolithophorids have attracted the attention of scientists interested in exploiting this ability for the development of materials science and biomedical and biotechnological applications. Although it has been well documented that biomineralization in E. huxleyi is promoted by growth under phosphate-limited conditions, the genes and proteins that govern the processes of calcification and coccolithogenesis remain unknown. Suppressive subtractive hybridization (SSH) libraries were constructed from cultures grown in phosphate-limited and phosphate-replete media as tester and driver populations for reciprocal SSH procedures. Positive clones from each of the two libraries were randomly selected, and dot blotting was performed for the analysis of expression patterns. A total of 513 clones from the phosphate-replete library and 423 clones from the phosphate-limited library were sequenced, assembled, and compared to sequences in GenBank using BLASTX. Of the 103 differentially expressed gene fragments from the phosphate-replete library, 34% showed significant homology to other known proteins, while only 23% of the 65 differentially expressed gene fragments from the phosphate-limited library showed homology to other proteins. To further assess mRNA expression, real-time RT-PCR analysis was employed and expression profiles were generated over a 14-day time course for three clones from the phosphate-replete library and five clones from the phosphate-limited library. The fragments isolated provide the basis for future cloning of full-length genes and functional analysis. 相似文献
67.
Daniel F. Austin Richard Felger Karol Chandler-Ezell Michael J. Balick Kurt Allerslev Reynertson Alfredo Gomez-Beloz My Lien T. Nguyen Rob Dean Neil A. Harriman Dorothea Bedigian Mary Theresa Bonhage-Freund Wendy Applequist Linda M. Lyon John Klock My Lien T. Nguyen 《Economic botany》2005,59(2):197-209
68.
Additional vertebrates and ostracods from the bituminous shale of the Khao Loc Formation at Tong Vai, Ha Giang Province, northern Vietnam, corroborate its correlation with the upper part of the Xishancun (Xiaxishancun) Formation and the lower part of the Xitun and Lianhuashan formations of South China, and its Middle to Late Lochkovian age. The variations in morphology and ornamentation of the galeaspid Polybranchiaspis liaojaoshanensis from Tong Vai are discussed and regarded as possibly size and growth-related. A new acanthothoracid placoderm with a very deep dorsal process is described from Tong Vai and the specific distinction between the antiarchs Minicrania lissa from Tong Vai and M. lirouyii from Yunnan is supported by additional characters. Petalichthyid placoderms are recorded from this locality for the first time, and the skull of a juvenile youngolepidid sarcopterygian is described. Eurypterid fragments and a phyllocarid crustacean are also recorded from the Khao Loc Formation. A new species of the chonetid brachiopod genus Tulynetes, endemic to northern Vietnam, is described from the Pragian Mia Le Formation at Cu Le, Bac Kan Province, a new locality which yields a large diversity of taxa with outstanding preservation. 相似文献
69.
Nathan R. Lien 《Inorganica chimica acta》2005,358(4):1284-1288
The crystal structure of Na[Co(NC6H6O6)] · H2O is reported. The structure is compared to similar transition-metal nitrilotriacetate complexes containing different alkali cations and transition metals (Cu2+ and Zn2+). Inner-sphere coordination of the metals is similar, but the arrangement of counter-ions and water molecules in the unit cells vary with the size of the alkali cation. 相似文献
70.