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71.
Luiz Garcia Mandarano-Filho Márcio Takey Bezuti Cláudio Henrique Barbieri 《Clinics (S?o Paulo, Brazil)》2016,71(3):140-144
OBJECTIVE:
The assessment of fracture union includes physical examination and radiographic imaging, which depend on the examiner''s experience. The development of ancillary methods may avoid prolonged treatments and the improper removal of implants. Quantitative bone ultrasonometry has been studied for this purpose and will soon be included in clinical practice. The aims of the present study were to assess the feasibility of using this technique on the clavicle and to standardize its in vivo application.METHODS:
Twenty adult volunteers, including 10 men and 10 women without medical conditions or a previous history of clavicle fracture, underwent axial quantitative ultrasonometric assessment using transducers in various positions (different distances between the transducers and different angulations relative to the clavicle).RESULTS:
Similar values of wave propagation velocity were obtained in the different tested set-ups, which included distinct distances between the transducers and angular positions relative to the clavicle. There were significant differences only in the transducers positioned at 0° and at 5 or 7 cm apart.CONCLUSIONS:
The use of bone ultrasonometry on the clavicle is feasible and the standardization of the technique proposed in this study (transducers placed at 45° and at 7 cm apart) will allow its future application in clinical trials to evaluate the healing process of diaphyseal fractures of the clavicle. 相似文献72.
Peretti V Ciotola F Albarella S Russo V Di Meo GP Iannuzzi L Roperto F Barbieri V 《Mutagenesis》2007,22(5):317-320
Chronic enzootic haematuria (CEH) is a severe syndrome due to prolonged ingestion of toxic principles of bracken fern, such as quercetin and ptaquiloside. Little information is available on chromosomal instability of cattle with access to bracken fern and suffering from CEH. In the present study, 45 cattle, aged from 7 to 12 years and pastured in the south of Italy, were cytogenetically investigated for the first time in search of both chromosomal aberrations (aneuploidy, gaps, chromatid breaks, chromosome breaks and fragments) and sister chromatid exchanges (SCEs). Of these animals, 30 (group 1) had access to bracken fern and showed signs of CEH, and 15 (group 2; control) did not. Percentage of abnormal cells (aneuploidy, chromatid breaks, chromosome breaks and fragments) was higher in animals affected by CEH (34.7%, group 1) than that (24.3%) reached in the control (group 2). The same results were achieved when including gaps. Indeed, the mean number of cells with structural aberrations excluding gaps (chromatid breaks, chromosome breaks and fragments) per cell was higher (P<0.001) in animals affected by CEH (0.16+/-0.36) than that (0.09+/-0.29) found in the control. Chromosome fragility in cells of animals affected by CEH was also confirmed when applying the SCE test: statistically higher levels (P<0.001) of SCEs were observed in animals with CEH (7.35+/-3.59 SCE/cell, group 1) than those in the control (5.40+/-2.68 SCE/cell). 相似文献
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75.
Barbieri F Pattarozzi A Gatti M Porcile C Bajetto A Ferrari A Culler MD Florio T 《Endocrinology》2008,149(9):4736-4746
Somatostatin inhibits cell proliferation through the activation of five receptors (SSTR1-5) expressed in normal and cancer cells. We analyzed the role of individual SSTRs in the antiproliferative activity of somatostatin in C6 rat glioma cells. Somatostatin dose-dependently inhibited C6 proliferation, an effect mimicked, with different efficacy or potency, by BIM-23745, BIM-23120, BIM-23206 (agonists for SSTR1, -2, and -5) and octreotide. The activation of SSTR3 was ineffective, although all SSTRs are functionally active, as demonstrated by the inhibition of cAMP production. All SSTRs induced cytostatic effects through the activation of the phosphotyrosine phosphatase PTPeta and the inhibition of ERK1/2. For possible synergism between SSTR subtypes, we tested the effects of the combined treatment with two agonists (SSTR1+2 or SSTR2+5) or bifunctional compounds. The simultaneous activation of SSTR1 and SSTR2 slightly increased the efficacy of the individual compounds with an IC50 in between the single receptor activation. SSTR2+5 activation displayed a pattern of response superimposable to that of the SSTR5 agonist alone (low potency and higher efficacy, as compared with BIM-23120). The simultaneous activation of SSTR1, -2, and -5 resulted in a response similar to somatostatin. In conclusion, the cytostatic effects of somatostatin in C6 cells are mediated by the SSTR1, -2, and -5 through the same intracellular pathway: activation of PTPeta and inhibition of ERK1/2 activity. Somatostatin is more effective than the individual agonists. The combined activation of SSTR1 and -2 shows a partial synergism as far as antiproliferative activity, whereas SSTR2 and -5 activation results in a response resembling the SSTR5 effects. 相似文献
76.
The HcrVf2 gene from a wild apple confers scab resistance to a transgenic cultivated variety 总被引:7,自引:0,他引:7 下载免费PDF全文
Belfanti E Silfverberg-Dilworth E Tartarini S Patocchi A Barbieri M Zhu J Vinatzer BA Gianfranceschi L Gessler C Sansavini S 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(3):886-890
The Vf gene from the wild species Malus floribunda 821 is the most studied apple scab resistance gene. Several molecular markers mapping around this gene were the starting point for a positional cloning project. The analysis of the bacterial artificial chromosome clones spanning the Vf region led to the identification of a cluster of genes homologous to the Cladosporium fulvum resistance gene family of tomato. One of these genes, HcrVf2 (homologue of the C. fulvum resistance genes of the Vf region), was used to transform the susceptible apple cultivar Gala. Four independent transformed lines resistant to apple scab were produced, proving that HcrVf2 is sufficient to confer scab resistance to a susceptible cultivar. The results show that direct gene transfer between cross-compatible species can be viable when, as in apple, the use of backcrosses to introduce resistance genes from wild species cannot exactly reconstitute the heterozygous genotype of clonally propagated cultivars. 相似文献
77.
A Z Belko M Van Loan T F Barbieri P Mayclin 《International journal of obesity (2005)》1987,11(2):93-104
The effect of a moderate energy intake plus exercise (MEEX) vs a low energy intake without exercise (LESD) on weight loss and energy expenditure was examined in two groups of moderately overweight women confined to a metabolic unit. An initial 2-week baseline period was used to determine weight maintenance energy requirement (ER). This was followed by a 6-week weight reduction period. Energy intake was decreased to 0.75 ER in MEEX and treadmill exercise was individually prescribed to increase energy expenditure to 1.25 ER. Energy intake was decreased to 0.5 ER in LESD. Thus, both energy intake and expenditure were manipulated to result in an energy deficit of 50 percent. Although total weight loss was significantly higher in LESD compared to MEEX (7.8 vs 5.7 kg), fat loss did not differ (5.1 vs 4.7 kg) hence the proportion of weight loss due to fat was greater in MEEX. Aerobic capacity, measured by maximum oxygen uptake, significantly improved in MEEX (2.44 to 2.84 l/min) but did not change in LESD (2.51 to 2.50 l/min). Basal metabolic rate, energy cost of standardized activities, and 3-hour thermic response to a test meal did not change in either group throughout the study. Thus, a 50 percent energy deficit, achieved by either diet alone or diet in combination with exercise, did not result in conservation of energy expenditure in moderately overweight women. 相似文献
78.
While it is known that mast cells arise from pluripotential hematopoietic cells and express their mature phenotypes in tissues, the sequence of events in maturation is incompletely understood. To study early mast cells, we sorted cells from interleukin-3 (IL-3)-dependent mouse bone marrow cultures on the basis of Fc epsilon RI and examined their morphology, histamine content, and growth characteristics. Flow cytometric analysis and sort showed that the Fc epsilon RI-bearing (Fc epsilon RI+) cells increased from 0% on day 0 to 90% by day 21 and that the total number of Fc epsilon RI+ cells increased from 0 at the start of culture to 3.75 x 10(5) cells by day 21 from an initial population of 1 x 10(5) cells. The dissociation rate of 125I-labeled IgE from early cultured cells resembled the dissociation rate of mouse IgE from mature murine mast cells. Mean fluorescence intensity increased over time, reflecting an increase in IgE receptor density. Fc epsilon RI+ cells were also positive for Fc gamma RII/III. Morphologic studies showed gradual acquisition of metachromatic granules in the Fc epsilon RI+ cells, which was paralleled by an increase in histamine content. Sorted Fc epsilon RI+ cells, when placed in liquid suspension culture, gave rise to pure mast cell populations. Fc epsilon RI+ cells sorted at day 3 and cultured in agarose with IL-3 gave rise to 4,800 small and 150 medium-size mast cell colony-forming units per 10(6) cells, while Fc epsilon RI- cells gave rise to 23 medium-size and 49 large mast cell colony-forming units per 10(6) cells. Fc epsilon RI+ cells grown in granulocyte-macrophage colony-stimulating factor (CSF) or macrophage-CSF did not give rise to colony-forming units. These results show that Fc epsilon RI+ cells have proliferative potential, but that there also is a population of mast cell progenitor cells that have not yet expressed Fc epsilon RI, and such individual progenitor cells have greater potential for proliferation than cells that express Fc epsilon RI. 相似文献
79.
The cytoskeleton in Chediak-Higashi syndrome fibroblasts 总被引:2,自引:0,他引:2
The Chediak-Higashi syndrome (CHS) trait is expressed in cultured human skin fibroblasts as an abnormal perinuclear concentration of moderately enlarged lysosomes. The cytoskeleton of CHS fibroblasts appears intact. Microtubules are normal in number and morphology, as assessed by colchicine binding studies, antitubulin immunofluorescence, and electron microscopy. Deformability by shear force is unaltered and microfilaments are abundant. However, CHS lysosomes appear to interact abnormally with the cytoskeleton, since the perinculear aggregation partially disperses after depolymerization of cell microtubules with colchicine. These results suggest that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane- microtubule interaction. 相似文献