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991.
Moreschi E Hernandes L Dantas JA da Silva MA Casaroto AR Bersani-Amado CA 《Histology and histopathology》2010,25(12):1547-1556
The aim of the present study was to evaluate histologically and radiographically the tissue response to dolomite [CaMg(CO3)2] and its osteogenic potential in the repair of bone cavities in the calvaria of rats. A bone defect 10 mm in diameter and 1 mm deep was made in the calvaria of male Wistar rats. The defects were filled with dolomite, inorganic bovine bone (positive control), or coagulum (negative control). The animals were euthanized 7, 15, 30, and 60 days after surgery, and specimens were collected for radiographic and microscopic analyses. The bone defects were processed for paraffin embedding and H&E staining. The histological study revealed that dolomite stimulated a moderate inflammatory response, with programmed cell death in the first 15 days, compared to bovine bone which showed a moderate to intense acute response. In the chronic phase, the inflammatory response was characterized by the occurrence of macrophages organized as epithelioid cells in the dolomite group, and giant cells in the bovine-bone group. Fibrosis developed in all three groups; however, encapsulation of the fragments, reabsorption, and osteoconductive activity occurred only in the defects filled with bovine bone. The radiographic analysis showed that the bovine bone was most efficient in the repair of the defects, followed by the dolomite and the coagulum. This study demonstrated that the dolomite stimulated a moderate acute inflammatory response with programmed cell death, and a chronic inflammatory response by means of the phagocytic mononuclear system. Although osteo-conductive activity was not shown, the dolomite favored the repair process, compared to the coagulum group. 相似文献
992.
Joo‐Yong Lee Waixing Tang Esther Wong Ya‐Sheng Gao Udai B Pandey Susmita Kaushik Emily Tresse Jianrong Lu J Paul Taylor Ana Maria Cuervo Tso‐Pang Yao 《The EMBO journal》2010,29(5):969-980
Autophagy is primarily considered a non‐selective degradation process induced by starvation. Nutrient‐independent basal autophagy, in contrast, imposes intracellular QC by selective disposal of aberrant protein aggregates and damaged organelles, a process critical for suppressing neurodegenerative diseases. The molecular mechanism that distinguishes these two fundamental autophagic responses, however, remains mysterious. Here, we identify the ubiquitin‐binding deacetylase, histone deacetylase‐6 (HDAC6), as a central component of basal autophagy that targets protein aggregates and damaged mitochondria. Surprisingly, HDAC6 is not required for autophagy activation; rather, it controls the fusion of autophagosomes to lysosomes. HDAC6 promotes autophagy by recruiting a cortactin‐dependent, actin‐remodelling machinery, which in turn assembles an F‐actin network that stimulates autophagosome–lysosome fusion and substrate degradation. Indeed, HDAC6 deficiency leads to autophagosome maturation failure, protein aggregate build‐up, and neurodegeneration. Remarkably, HDAC6 and F‐actin assembly are completely dispensable for starvation‐induced autophagy, uncovering the fundamental difference of these autophagic modes. Our study identifies HDAC6 and the actin cytoskeleton as critical components that define QC autophagy and uncovers a novel regulation of autophagy at the level of autophagosome–lysosome fusion. 相似文献
993.
Jelena Djordjevic Ana Djordjevic Miroslav Adzic Marija B. Radojcic 《Cellular and molecular neurobiology》2010,30(5):693-700
Chronic neuroendocrine stress usually leads to the elevation of the stress hormones and increased metabolic rate, which is
frequently accompanied by oxidative damage to the CNS. In the present study we hypothesized that chronic psychosocial isolation
(CPSI) of male Wistar rats, characterized by decreased serum corticosterone (CORT), unaltered catecholamines (CTs), and low
blood glucose (GLU), may also promote oxidative imbalance in the CNS, by targeting antioxidant defense system. To test it,
we have examined the relation between these input signals and protein expression/activity of antioxidant enzymes (AOEs): superoxide
dismutases (SODs), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GLR) in the hippocampus (HIPPO)
of CPSI animals. We found that CPSI did not affect SODs or CAT, but decreased activity of GPx and compromised GLR, an enzyme
highly dependent on blood GLU for its substrate precursor. Further, we have tested whether the CPSI experience altered AOEs
response to a novelty stress, and found that it attenuated peroxide-metabolizing enzymes, CAT and GPx, and decreased GLR activity,
even though blood GLU was restored. The altered ratios of hippocampal AOEs in CPSI animals, which were worsened under the
combined stress conditions, may lead to the accumulation of peroxide products and oxidative imbalance. The mechanism by which
CPSI generate oxidative imbalance in the HIPPO is most likely based on poor systemic energy conditions set by this stress.
Such conditions may cause functional decline of CNS structures, such as HIPPO, and are likely to promote state linked to onset
of many mood disorders. 相似文献
994.
995.
Bárbara Santos Pires da Silva Eloísa Bonfá Júlio César Bertacini de Moraes Carla Gonçalves Schain Saad Ana Cristina de Medeiros Ribeiro Célio Roberto Gonçalves Jozélio Freire de Carvalho 《Biologicals》2010,38(5):567-569
The objective of this study was to evaluate the influence of anti-tumor necrosis factor (anti-TNF) in juvenile idiopathic arthritis (JIA), ankylosing spondylitis (AS) or psoriatic arthritis (PsA). Sixty-two patients were investigated: 7 JIA; 37 AS; and 18 PsA. Caucasian race accounted for 79% and 29% were female. Mean age was 40.4 ± 12.6years. None of the patients had a history of diabetes, and none had used oral hypoglycemic agents or insulin. Treatment was with adalimumab, infliximab and etanercept. Glucose, inflammatory markers and prednisone dose were assessed at baseline, as well as after three and six months of treatment. The mean erythrocyte sedimentation rate was significantly lower at three months and six months than at baseline (13.7 ± 18.0 and 18 ± 22.5 vs. 27.9 ± 23.4 mm; p = 0.001). At baseline, three months and six months, we found the following: mean C-reactive protein levels were comparable (22.1 ± 22.7, 14.5 ± 30.7 and 16.0 ± 23.8 mg/L, respectively; p = 0.26); mean glucose levels remained unchanged (90.8 ± 22.2 mg/dl, 89.5 ± 14.6 mg/dl and 89.8 ± 13.6 mg/dl, respectively; p = 0.91); and mean prednisone doses were low and stable (3.9 ± 4.9 mg/day, 3.7 ± 4.8 mg/day and 2.6 ± 4.0 mg/day, respectively; p = 0.23). During the first six months of treatment, anti-TNF therapy does not seem to influence glucose metabolism in JIA, AS or PsA. 相似文献
996.
Given the demand for improved methods for detecting and characterizing RNA variants in situ, we developed a quantitative method for detecting RNA alternative splicing variants that combines in situ hybridization of fluorescently labeled peptide nucleic acid (PNA) probes with confocal microscopy Förster resonance energy transfer (FRET). The use of PNA probes complementary to sequences flanking a given splice junction allows to specifically quantify, within the cell, the RNA isoform generating such splice junction as FRET efficiency measure. The FRET-based PNA fluorescence in situ hybridization (FP-FISH) method offers a conceptually new approach for characterizing at the subcellular level not only splice variant isoform structure, location, and dynamics but also potentially a wide variety of close range RNA–RNA interactions. In this paper, we explain the FP-FISH technique workflow for reliable and reproducible results. 相似文献
997.
Ana Paula Chiaverini Pinto Alessandra Cristina B. A. Monteiro-Hara Liliane Cristina Liborio Stipp Beatriz Madalena Januzzi Mendes 《In vitro cellular & developmental biology. Plant》2010,46(1):28-33
Passiflora alata in vitro organogenesis was studied based on explant type, culture medium composition, and incubation conditions. The results indicated
that the morphogenic process occurred more efficiently when hypocotyl segment-derived explants were cultured in media supplemented
with cytokinin and AgNO3 incubated under a 16-h photoperiod. The shoot bud elongation and plant development were obtained by transferring the material
to MSM culture medium supplemented with GA3 and incubated in flasks with vented lids. Histological analyses of the process revealed that the difficulties in obtaining
plants could be related to the development of protuberances and leaf primordia structures, which did not contain shoot apical
meristem. Roots developed easily by transferring elongated shoots to 1/2 MSM culture medium. Plant acclimatization occurred
successfully, and somaclonal variation was not visually detected. The efficiency of this organogenesis protocol will be evaluated
for genetic transformation of this species to obtain transgenic plants expressing genes that can influence the resistance
to Cowpea aphid borne mosaic virus. 相似文献
998.
The impact of cold-water immersion on power production in the vertical jump and the benefits of a dynamic exercise warm-up 总被引:1,自引:0,他引:1
Dixon PG Kraemer WJ Volek JS Howard RL Gomez AL Comstock BA Dunn-Lewis C Fragala MS Hooper DR Häkkinen K Maresh CM 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(12):3313-3317
The purpose of this study was to examine the influence of a cold treatment and a dynamic warm-up on lower body power in the form of a countermovement vertical jump (CMVJ). Nine physically active men, who were either current or ex-National Collegiate Athletic Association (NCAA) Division 1 athletes, consented to participate in the study. Using a balanced, randomized presentation and a within-subject design, each subject performed 4 environmental and warm-up protocols (i.e., ambient temperature without warm-up, ambient temperature with warm-up, cold without warm-up, or cold with warm-up). Two sets of 3 maximal effort CMVJs were performed on a force plate at each testing time point. For each protocol, the subjects completed a pretest set of CMVJ (pretreatment [PRE]), were then exposed to 1 of the 2 temperature treatments, completed another set of CMVJ (initial [IT]), then either went through a 15-minute warm-up, or were asked to sit in place. Then a final set of CMVJs was completed (posttreatment [PT]). The primary finding in this study was that warm-up was effective in offsetting the negative effects of cold exposure on CMVJ power. There was a significant main effect for Time (PRE > PT > IT), and there was a significant (p ≤ 0.05) main effect for Trial (AMB = AMBWU > COLDWU > COLD). Because athletic competitions happen in various colder climates, it is important to make sure that a proper warm-up be completed to maximize the athlete's power output. The results of this study demonstrate that when athletes are exposed to cold conditions, it is recommended that before practice or play, a dynamic warm-up be employed to optimize performance. 相似文献
999.
Ana Flávia Azevedo Carvalho Maurício Boscolo Roberto da Silva Henrique Ferreira Eleni Gomes 《Journal of microbiology (Seoul, Korea)》2010,48(4):452-459
An α-glucosidase enzyme produced by the fungus Thermoascus aurantiacus CBMAI 756 was purified by ultra filtration, ammonium sulphate precipitation, and chromatography using Q Sepharose, Sephacryl
S-200, and Superose 12 columns. The apparent molecular mass of the enzyme was 83 kDa as determined in gel electrophoresis.
Maximum activity was observed at pH 4.5 at 70°C. Enzyme showed stability stable in the pH range of 3.0–9.0 and lost 40% of
its initial activity at the temperatures of 40, 50, and 60°C. In the presence of ions Na+, Ba2+, Co2+, Ni2+, Mg2+, Mn2+, Al3+, Zn2+, Ca2+ this enzyme maintained 90–105% of its maximum activity and was inhibited by Cr3+, Ag+, and Hg2+. The enzyme showed a transglycosylation property, by the release of oligosaccharides after 3 h of incubation with maltose,
and specificity for short maltooligosaccharides and α-PNPG. The Km measured for the α-glucosidase was 0.07 μM, with a Vmax of 318.0 μmol/min/mg. 相似文献
1000.
Fernando Rodríguez‐Serrano Pablo Álvarez Octavio Caba Manuel Picón Juan A. Marchal Macarena Perán José Prados Consolación Melguizo Ana R. Rama Houria Boulaiz Antonia Aránega 《Cell biology international》2010,34(9):917-924
Adult stem cells are becoming the best option for regenerative medicine because they have low tumourigenic potential and permit autologous transplantation, even without in vitro culture. Our objectives were to evaluate the effects of exogenous nucleosides on the proliferation of hASCs (human adipose‐derived stem cells), with or without co‐treatment with 5‐aza (5‐azacytidine), and to analyse the expression of lamin A/C during cardiomyocyte differentiation of these cells. We isolated hASCs from human lipoaspirates that were positive for mesenchymal stem cell markers. We found that 5‐aza induces a dose‐dependent inhibition of hASC proliferation [IC50 (inhibitory concentration 50): 5.37 μM], whereas exogenous nucleosides significantly promote the proliferation of hASCs and partially revert the antiproliferative effect of the drug. Multipotentiality of isolated hASCs was confirmed by adipogenic, osteogenic and cardiomyogenic induction. 5‐Aza‐induced cells expressed cardiac troponins I and T and myosin light chain 2, myocardial markers that were directly correlated with lamin A/C expression. Our results support the importance of the nucleoside supplementation of media to improve conditions for the expansion and maintenance of hASCs in culture. In addition, the quantification of lamin A/C expression appears to be a good marker for the characterization of cardiomyocyte differentiation of stem cells that has rarely been used. 相似文献