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111.
Cellular cardiomyoplasty: development of a technique to culture human myoblasts for clinical transplantation 总被引:2,自引:0,他引:2
Vázquez ME Cabarcos MR Román TD Stein AJ Garcia ND Nazar BA Dopico MJ Núñez CA Garcia FJ 《Cell and tissue banking》2005,6(2):117-124
Some recent studies have demonstrated that epicardial injection of autologous myoblasts, obtained from satellite cells of skeletal muscle, in association to coronary artery bypass graft surgery (CABG) in patients with decreased left ventricular function secondary to ischaemic disease could be of some utility to get a better recovery of ventricular function due to the ability of these cells to grow and generate new muscle fibers over the previous fibrotic scar. The aims are the setting up of a process for the collection of the cellular cardiomyoplasty in samples of multiorganic donations and to carry out this technique in the same surgical moment as the revascularisation is performed in two patients. For this purpose we obtained muscle through biopsy of 15 human multiorgan donors and of two patients. Separation of fatty tissue, minced, and further digestion with collagenase type I (1.5 mgr/ml/2 gr by weight) and trypsin 1 ×. Filtration of the cellular suspension, centrifugation and sowing of this suspension in culture medium, with 20% of human serum. Culture for three weeks until obtainment of between 200–300 million cells. Inmunohistochemistry and flow cytometry for the identification of the myoblasts was carried out. The results were obtained through flow cytometry, using CD56 as an indicator of the presence of myoblasts, between 70 and 80% of these types of cells were obtained after three weeks of culture. By inmunohistochemistry analyses, different markers were analyzed: desmin and myogenin. The results indicated the presence of a great number of positive cells with these markers, possibly myoblasts. Skeletal myoblast implant was not associated with adverse effects. The culture of autologous myoblasts is a rapid and simple technique where after three weeks of culture a great number of cells for implantation are obtained. In patients with old myocardial infarction, treatment with skeletal myoblast in conjunction with coronary artery bypass is safe and feasible. and it is easy to obtain myoblasts from muscle tissue for transplant into patients. 相似文献
112.
Berta Dopico Francisco José Muñoz Gregorio Nicolás Emilia Labrador 《Physiologia plantarum》1991,83(4):659-663
The autolytic process in epicotyl cell walls of Cicer arietinum L. cv. Castellana, and also the hydrolysis of heat-inactivated cell walls as mediated by a cell wall β-galactosidase (EC 3.2.1.23) (named βIII and previously characterized as responsible for the autolysis), are maximal on the fourth day of germination and coincide with the maximal growth capacity. They decrease during the following days, in which the growth rate diminishes. In both cases, no differences were observed in the percentages of the different sugars released, galactose being the principal one. The βIII fraction from aged epicotyl cell walls hydrolyzed young walls in proportion to its specific activity, and more efficient than when cell walls from aged material were used as the substrate. The βIII fraction from 4 day-old epicotyls (the time for maximal autolysis) was incapable of hydrolyzing aged epicotyl cell walls to the same extent as young ones. These results, together with the levels and activity of the enzyme throughout growth, allow the assumption that the variations in the autolysis and hydrolysis caused by βIII during growth processes are due to structural modifications in the cells walls, modifications that would limit access of the enzyme to its substrate, thus impeding the release of galactose, even though the enzyme is present. 相似文献
113.
Lotus corniculatus nodulation specificity is changed by the presence of a soybean lectin gene 总被引:5,自引:0,他引:5
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Plant lectins have been implicated as playing an important role in mediating recognition and specificity in the Rhizobium-legume nitrogen-fixing symbiosis. To test this hypothesis, we introduced the soybean lectin gene Le1 either behind its own promoter or behind the cauliflower mosaic virus 35S promoter into Lotus corniculatus, which is nodulated by R. loti. We found that nodulelike outgrowths developed on transgenic L. corniculatus plant roots in response to Bradyrhizobium japonicum, which nodulates soybean and not Lotus spp. Soybean lectin was properly targeted to L. corniculatus root hairs, and although infection threads formed, they aborted in epidermal or hypodermal cells. Mutation of the lectin sugar binding site abolished infection thread formation and nodulation. Incubation of bradyrhizobia in the nodulation (nod) gene-inducing flavonoid genistein increased the number of nodulelike outgrowths on transgenic L. corniculatus roots. Studies of bacterial mutants, however, suggest that a component of the exopolysaccharide surface of B. japonicum, rather than Nod factor, is required for extension of host range to the transgenic L. corniculatus plants. 相似文献
114.
115.
Fitness effects of amino acid replacements in the beta-galactosidase of Escherichia coli 总被引:7,自引:1,他引:6
Two genetic procedures were used to obtain amino acid replacements in the
lacZ-encoded beta-galactosidase in Escherichia coli. Amino acid
replacements could be obtained without regard to their effects on lactase
activity by selecting spontaneous mutations that relieved the strong
polarity of six nonsense mutations. When streaked on MacConkey- lactose
indicator plates, approximately 75% of these mutants gave strong red
lactose-fermenting colonies, and 25% gave white nonfermenting colonies.
Mutants from 11 other nonsense codons were isolated directly using
MacConkey-lactose indicator plates, on which positive color indication
requires only 0.5% of the wildtype lactase activity. Among the total of 17
codons, 25 variant beta-galactosidases were identified using
electrophoresis and thermal denaturation studies. The fitness effects of
these variant beta-galactosidases were determined using competition
experiments conducted with lactose as the sole nutrient limiting the growth
rate in chemostat cultures. Three of the replacements were deleterious, one
was selectively advantageous, and the selective effects of the remaining 21
were undetectable under conditions in which the smallest detectable
selection coefficient was approximately 0.4%/generation.
相似文献
116.
RC Pritchett AM Al-Nawaiseh KK Pritchett V Nethery PA Bishop JM Green 《Biology of sport / Institute of Sport》2015,32(3):249-254
Sweat production is crucial for thermoregulation. However, sweating can be problematic for individuals with spinal cord injuries (SCI), as they display a blunting of sudomotor and vasomotor responses below the level of the injury. Sweat gland density and eccrine gland metabolism in SCI are not well understood. Consequently, this study examined sweat lactate (S-LA) (reflective of sweat gland metabolism), active sweat gland density (SGD), and sweat output per gland (S/G) in 7 SCI athletes and 8 able-bodied (AB) controls matched for arm ergometry VO2peak. A sweat collection device was positioned on the upper scapular and medial calf of each subject just prior to the beginning of the trial, with iodine sweat gland density patches positioned on the upper scapular and medial calf. Participants were tested on a ramp protocol (7 min per stage, 20 W increase per stage) in a common exercise environment (21±1°C, 45-65% relative humidity). An independent t-test revealed lower (p<0.05) SGD (upper scapular) for SCI (22.3 ±14.8 glands · cm−2) vs. AB. (41.0 ± 8.1 glands · cm−2). However, there was no significant difference for S/G between groups. S-LA was significantly greater (p<0.05) during the second exercise stage for SCI (11.5±10.9 mmol · l−1) vs. AB (26.8±11.07 mmol · l−1). These findings suggest that SCI athletes had less active sweat glands compared to the AB group, but the sweat response was similar (SLA, S/G) between AB and SCI athletes. The results suggest similar interglandular metabolic activity irrespective of overall sweat rate. 相似文献
117.
Elaine A Dunlop Sara Seifan Tijs Claessens Christian Behrends Miriam AF Kamps Ewelina Rozycka Alain J Kemp Ravi K Nookala John Blenis Barry J Coull James T Murray Maurice AM van Steensel Simon Wilkinson Andrew R Tee 《Autophagy》2014,10(10):1749-1760
Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal dominant condition caused by mutations in the FLCN gene and characterized by benign hair follicle tumors, pneumothorax, and renal cancer. Folliculin (FLCN), the protein product of the FLCN gene, is a poorly characterized tumor suppressor protein, currently linked to multiple cellular pathways. Autophagy maintains cellular homeostasis by removing damaged organelles and macromolecules. Although the autophagy kinase ULK1 drives autophagy, the underlying mechanisms are still being unraveled and few ULK1 substrates have been identified to date. Here, we identify that loss of FLCN moderately impairs basal autophagic flux, while re-expression of FLCN rescues autophagy. We reveal that the FLCN complex is regulated by ULK1 and elucidate 3 novel phosphorylation sites (Ser406, Ser537, and Ser542) within FLCN, which are induced by ULK1 overexpression. In addition, our findings demonstrate that FLCN interacts with a second integral component of the autophagy machinery, GABA(A) receptor-associated protein (GABARAP). The FLCN-GABARAP association is modulated by the presence of either folliculin-interacting protein (FNIP)-1 or FNIP2 and further regulated by ULK1. As observed by elevation of GABARAP, sequestome 1 (SQSTM1) and microtubule-associated protein 1 light chain 3 (MAP1LC3B) in chromophobe and clear cell tumors from a BHD patient, we found that autophagy is impaired in BHD-associated renal tumors. Consequently, this work reveals a novel facet of autophagy regulation by ULK1 and substantially contributes to our understanding of FLCN function by linking it directly to autophagy through GABARAP and ULK1. 相似文献
118.
119.
120.
QualitySNP: a pipeline for detecting single nucleotide polymorphisms and insertions/deletions in EST data from diploid and polyploid species 总被引:2,自引:0,他引:2
Jifeng Tang Ben Vosman Roeland E Voorrips C Gerard van der Linden Jack AM Leunissen 《BMC bioinformatics》2006,7(1):438