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991.
Nowak E Brousseau R Garrett J Masson L Maynard C Trevors JT Edge TA 《Canadian journal of microbiology》2008,54(5):380-390
Two commercial products, Biotize and Cycle, containing bacteria as an active ingredient were characterized for species identification and batch-to-batch variation by denaturing gradient gel electrophoresis (DGGE), total cellular fatty acid analysis (FAA), and a taxonomic DNA microarray. DGGE was useful at assessing the stability of consortia in different batches, and cluster analysis differentiated each batch even when only slight differences in species composition were observed. DGGE, FAA, and DNA microarray results indicated little batch-to-batch variation in Biotize and some batch variation in Cycle. The 3 methods agreed well with species identification in Biotize but generated conflicting results in the species composition of Cycle. This multi-method approach was useful in determining if the observed bacterial species present in the products matched the expected species composition. 相似文献
992.
King CG Buckler JL Kobayashi T Hannah JR Bassett G Kim T Pearce EL Kim GG Turka LA Choi Y 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(1):34-38
TRAF6, TNFR-associated factor 6, is a key adaptor downstream from the TNF receptor and TLR superfamily members. T cell-specific deletion of TRAF6 (TRAF6-DeltaT) was recently shown to result in the development of multiorgan inflammatory disease and the resistance of responder T cells to suppression by CD4+CD25+ regulatory T cells. In this study we examined the role of TRAF6 in an additional mechanism of peripheral tolerance, anergy. We have determined that the loss of TRAF6 restores the ability of CD28-/- T cells to proliferate and produce IL-2. Consistent with this, TRAF6-DeltaT T cells were resistant to anergizing signals both in vitro and in vivo. Resistance to anergy was correlated with decreased expression of Cbl-b. These findings reveal that in addition to its role in rendering T cells susceptible to control by CD4+CD25+ regulatory T cells, TRAF6 is essential for the induction of T cell anergy, implicating TRAF6 as a critical mediator of peripheral tolerance. 相似文献
993.
The study of undecalcified bone by histological methods is essential in the field of bone research. Culturing skeletal tissues such as neonatal murine calvaria provides a reliable bridge between assessment of bone formation in vitro and anabolic activity in vivo and contains most of the essential elements of bone for studying bone formation. Neonatal calvarial assay, supported by histological methods, is used to study the anabolic effects of a wide variety of factors and compounds on bone tissue. To optimize visualization and histomorphometric measurements using neonatal calvaria, we developed a method that provides high quality tissue sections suitable for routine and histochemical staining. Undecalcified neonatal mouse calvaria were processed and embedded using a low temperature methyl methacrylate procedure. Various staining methods were performed on deplastisized and floated sections to examine mineralization and to identify cells. The Von Kossa stain counterstained with a modified H & E yielded precise images of unmineralized bone including mineralization sites, and distinct osteoblasts and osteoclasts. Toluidine blue, Ladewig's trichrome, tartrate-resistant acid phosphatase, Goldner, H & E and Villanueva stains also were tested on the undecalcified neonatal calvaria sections. 相似文献
994.
Tristan Montier Pascal Delépine Rémi Marianowski Karine Le Ny Morgane Le Bris Danielle Gillet Gaël Potard Philippe Mondine Irène Frachon Jean-Jacques Yaouanc Jean-Claude Clément Hervé des Abbayes Claude Férec 《Molecular biotechnology》2004,26(3):193-205
Cystic fibrosis (CF) is the most common autosomal lethal recessive disorder in the Caucasian population. The major cause of
mortality is lung disease, owing to the failure of a functional protein from the cystic fibrosis transmembrane conductance
regulator (CFTR) gene. Today, even though the knowledge about the CFTR genomic is extensive, no efficient treatment has been
developed yet.
In this context, gene therapy represents a potential important advance on condition that it could develop efficient and safe
transfection agents. Even though viral vectors have been used in most clinical trials owing to their high transfection efficiency,
random integration and immunogenicity are still critical side effects. Consequently, all of these drawbacks brought forth
the development of nonviral transfection systems. Although they engender few toxicity and immunogenicity problems, their low
transfection efficiency is a hurdle that must be overcome. Over the past decade, we have developed an original family of monocationic
lipids, cationic phosphonolipids, whose efficiency has been previously demonstrated both in vitro and in vivo.
In this report, we observe that a new cationic phosphonolipid (KLN 30) can lead to the restoration of the CFTR protein following
the ex vivo transfection of epithelial cells issuing from a ΔF508 homozygous patient. The transgene expression and the cytotoxicity
correlate with the charge ratio of the lipoplex. A kinetic study was performed, and a luminescent signal was detected until
35 d after transfection. 相似文献
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Near-ultraviolet survival of colony forming ability was compared between fibroblast strains from normal individuals and seven strains from Bloom's Syndrome patients using monochromatic light at 313 nm. Six BS strains possessed abnormal survival properties. Two strains lacked the low dose shoulder, which is characteristic for normal fibroblasts, but their overall sensitivity was in the normal range. Four BS strains were hypersensitive and possessed biphasic survival curves with a sharp initial drop. They mimick in culture the characteristic solar sensitivity of BS patients. 相似文献
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J E Garrett R D Geisert M T Zavy L K Gries R P Wettemann D S Buchanan 《Prostaglandins》1988,36(1):85-96
The present study was developed to determine if administration of progesterone, early in the estrous cycle of the cow, stimulated an advanced pulsatile release of PGF2 alpha from the uterine endometrium resulting in a decreased interestrous interval. Twenty-three cyclic beef cows were randomly assigned to receive either sesame oil or progesterone (100 mg) on Day 1, 2, 3 and 4 of the estrous cycle. Peripheral plasma concentrations of progesterone and the metabolite of prostaglandin F2 alpha, 15-keto-13,14-dihydro-prostaglandin F2 alpha (PGFM) were measured by radioimmunoassay. Administration of exogenous progesterone increased peripheral plasma concentration of progesterone in treated (3.67 ng/ml) compared to control (1.28 ng/ml) cows from Day 2 through 5 of the estrous cycle. Progesterone administration shortened the interestrous interval (16.7 d) compared to controls (21.6 d). The shortened interestrous intervals in treated cows resulted from an earlier decline in peripheral plasma progesterone. Decline of peripheral plasma progesterone concentrations is coincident with an increased pulsatile release of PGFM in both progesterone treated and control cows. Results indicate that administration of exogenous progesterone stimulates an earlier maturation of endometrial development, causing an advanced release of PGF2 alpha which shortens the interestrous interval of the cow. 相似文献