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101.
Guerino MR Luciano E Goncalves M Leivas TP 《Physiological chemistry and physics and medical NMR》1999,31(2):131-138
The objective of this study was to investigate the effects of ultrasound treatment and physical exercise on the velocity of bone consolidation and resistance to deformation. We performed osteotomy in the upper third of the right tibia of rats. Physical training consisted of swimming 1 h per day with a load of 5% b.w. for 30 days. Therapy with medium-intensity ultrasound was applied daily on the damaged area. Wistar rats were divided into the following groups: osteotomized sedentary animals with no ultrasound treatment (1.OSnUS), osteotomized trained animals with no ultrasound treatment (2.OTnUS), osteotomized sedentary animals with ultrasound treatment (3.OSwUS), and osteotomized trained animals with ultrasound treatment (4.OTwUS). The animals were sacrificed for the following analyses: muscle glycogen, serum alkaline phosphatase at the 5th, 10th, 20th, and 30th days, test of maximum resistance to flexion, rupture flexion and mean tibial rigidity at the 30th day. Muscle glycogen was increased at the 20th day; alkaline phosphatase was elevated at the 5th and 20th days in groups 3.OSwUS and 4.OTwUS, and decreased at the 10th day. Groups 1.OSnUS and 2.OTnUS did not show significant variations. In the mechanical resistance tests, we noted that ultrasound therapy and the association of physical activity used in the present study showed significant differences in bone resistance and bone rigidity after 30 days of treatment. These facts suggest that ultrasound or physical activity, or their combination may accelerate the process of bone tissue repair. 相似文献
102.
Effect of different growth hormone dosages on the growth velocity in children born small for gestational age 总被引:3,自引:0,他引:3
To assess whether short-term growth hormone (GH) treatment can improve the linear growth in children who were born small for gestational age (SGA), we started a randomized multicenter trial in 26 age- and sex-matched prepubertal children born SGA. During the 1st year of GH therapy, all children received GH 0.23 mg/kg/week, then during the 2nd year, 13 children received the same dose (group A), and in the other 13 children, the dose of GH was doubled, i.e., 0.46 mg/kg/week (group B). During the 1st year of therapy, the growth velocity significantly (p<0.0001) increased in all patients. During the 2nd year, group A showed a significant decrease of the growth velocity (p<0.015), whereas group B maintained the growth rate. The height in group A children significantly increased during the 1st and the 2nd year of GH therapy (p<0.000002 and p<0.000001, respectively), reaching the normal range in 8 out of 13 children at the end of 2 years of GH therapy. The height in group B children significantly increased during the 1st and the 2nd year of GH therapy (p<0.000001 and p<0.000001, respectively), reaching the normal range in all 11 children who completed the GH therapy. The height gain was similar in groups A and B treated with the same GH dosage during the 1st year of therapy. A greater increase in height gain was found in children of group B treated with the higher GH dosage during the 2nd year of therapy as compared with group A (p<0.02). Significant increases in insulin-like growth factor I (p<0.0001), acid-labile subunit (p<0.0002), and bone/chronological age ratio (p<0.0001) were found after the 1st year of GH therapy, but no significant changes were observed during the 2nd year, independently of the GH dose. In conclusion, the height velocity of children born SGA significantly increases during the 1st year of GH therapy, diminishes, but can decrease during the 2nd year, if the GH dosage is not raised. 相似文献
103.
Beneficial effects of GH/IGF-1 on skeletal muscle atrophy and function in experimental heart failure 总被引:10,自引:0,他引:10
Dalla Libera L Ravara B Volterrani M Gobbo V Della Barbera M Angelini A Danieli Betto D Germinario E Vescovo G 《American journal of physiology. Cell physiology》2004,286(1):C138-C144
Muscle atrophy is a determinant of exercise capacity in heart failure (CHF). Myocyte apoptosis, triggered by tumor necrosis factor- (TNF-) or its second messenger sphingosine (SPH), is one of the causes of atrophy. Growth hormone (GH) improves hemodynamic and cardiac trophism in several experimental models of CHF, but its effect on skeletal muscle in CHF is not yet clear. We tested the hypothesis that GH can prevent skeletal muscle apoptosis in rats with CHF. CHF was induced by injecting monocrotaline. After 2 wk, 2 groups of rats were treated with GH (0.2 mg·kg1·day1 and 1.0 mg·kg1·day1) subcutaneously. A third group of controls had saline. After 2 additional weeks, rats were killed. Tibialis anterior cross-sectional area, myosin heavy chain (MHC) composition, and a study on myocyte apoptosis and serum levels of TNF- and SPH were carried out. The number of apoptotic nuclei, muscle atrophy, and serum levels of TNF- and SPH were decreased with GH at high but not at low doses compared with CHF rats. Bcl-2 was increased, whereas activated caspases and bax were decreased. The MHC pattern in GH-treated animals was similar to that of controls. Monocrotaline slowed down both contraction and relaxation but did not affect specific tetanic force, whereas absolute force was decreased. GH treatment restored contraction and relaxation to control values and brought muscle mass and absolute twitch and tetanic tension to normal levels. These findings may provide an insight into the therapeutic strategy of GH given to patients with CHF to improve exercise capacity. apoptosis; cytokines; myosin heavy chains 相似文献
104.
Varela ES Lima JP Galdino AS Pinto Lda S Bezerra WM Nunes EP Alves MA Grangeiro TB 《Phytochemistry》2004,65(1):59-69
The complete sequences of nuclear ribosomal DNA (nrDNA) internal transcribed spacer regions (ITS/5.8S) were determined for species belonging to six genera from the subtribe Diocleinae as well as for the anomalous genera Calopogonium and Pachyrhizus. Phylogenetic trees constructed by distance matrix, maximum parsimony and maximum likelihood methods showed that Calopogonium and Pachyrhizus were outside the clade Diocleinae (Canavalia, Camptosema, Cratylia, Dioclea, Cymbosema, and Galactia). This finding supports previous morphological, phytochemical, and molecular evidence that Calopogonium and Pachyrhizus do not belong to the subtribe Diocleinae. Within the true Diocleinae clade, the clustering of genera and species were congruent with morphology-based classifications, suggesting that ITS/5.8S sequences can provide enough informative sites to allow resolution below the genus level. This is the first evidence of the phylogeny of subtribe Diocleinae based on nuclear DNA sequences. 相似文献
105.
106.
UBP10 encodes a deubiquitinating enzyme of Saccharomyces cerevisiae. Its inactivation results in a complex phenotype characterized by a subpopulation of cells that exhibits the typical cellular markers of apoptosis. Here, we show that additional deletion of YCA1, coding for the yeast metacaspase, suppressed the ubp10 disruptant phenotype. Moreover, YCA1 overexpression, without any external stimulus, had a detrimental effect on growth and viability of ubp10 cells accompanied by an increase of apoptotic cells. This response was completely abrogated by ascorbic acid addition. We also observed that cells lacking UBP10 had an endogenous caspase activity, revealed by incubation in vivo with FITC-labeled VAD-fmk. All these results argue in favour of an involvement of the yeast metacaspase in the active cell death triggered by loss of UBP10 function. 相似文献
107.
Magliani W Conti S Salati A Vaccari S Ravanetti L Maffei DL Polonelli L 《FEMS yeast research》2004,5(1):11-18
This review focuses on the potential of yeast killer toxin (KT)-like antibodies (KTAbs), that mimic a wide-spectrum KT through interaction with specific cell wall receptors (KTR) and their molecular derivatives (killer mimotopes), as putative new tools for transdisease anti-infective therapy. KTAbs are produced during the course of experimental and natural infections caused by KTR-bearing micro-organisms. They have been produced by idiotypic vaccination with a KT-neutralizing mAb, also in their monoclonal and recombinant formats. KTAbs and KTAbs-derived mimotopes may exert a strong therapeutic activity against mucosal and systemic infections caused by eukaryotic and prokaryotic pathogenic agents, thus representing new potential wide-spectrum antibiotics. 相似文献
108.
109.
The interaction of water with flour or gluten in hydrated samples was investigated by proton magnetization transfer measurements. Flour and gluten from both durum and bread wheat seeds, either unaged or artificially aged over different periods of time, were investigated. Measurements were performed at several radio frequency power levels and frequency offsets, and the data were quantitatively modeled by two interacting pools, a liquid (water) and a solid (macromolecules) one. A super-Lorentzian line shape well described the magnetization of the solid pool. Magnetization transfer was found to be more efficient for flour with respect to gluten samples, in agreement with their hydrophilic/hydrophobic behavior. The aging treatment of seeds resulted in a minor degree of interaction between macromolecules and water. 相似文献
110.
Structural study of four-stranded quadruplex structures containing 2'-deoxy-8-(propyn-1-yl)adenosine
Esposito V Randazzo A Galeone A Varra M Mayol L 《Bioorganic & medicinal chemistry》2004,12(5):1191-1197
In this paper, we report the NMR structural study of two quadruplex structures formed by truncations of the human telomeric sequence and containing a modified base, namely d(AprGGGT) and d(TAprGGGT), where Apr indicates 2'-deoxy-8-(propyn-1-yl)adenosines. Both oligonucleotides have been found to form 4-fold symmetric G-quadruplex structures with all strands parallel and equivalent to each other and characterized by higher thermal stabilities than the natural counterparts. The presence of the propynyl groups affects the conformations of the 5' edge of both quadruplexes in such a way to prevent the formation of one of the two possible H-bond patterns observed for a canonical A-tetrad. The increased thermal stabilities of the modified quadruplexes seem to be mostly due to a prevalent syn glycosidic conformation assumed by the Apr residues. 相似文献