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941.
942.
Tariq Ezaz Denis O’Meally Alexander E. Quinn Stephen D. Sarre Arthur Georges Jennifer A. Marshall Graves 《Cytotechnology》2008,58(3):135-139
Primary cell lines were established from cultures of tail and toe clips of five species of Australian dragon lizards: Tympanocryptis pinguicolla, Tympanocryptis sp., Ctenophorus fordi, Amphibolurus norrisi and Pogona vitticeps. The start of exponential cell growth ranged from 1 to 5 weeks. Cultures from all specimens had fibroblastic morphology.
Cell lines were propagated continuously up to ten passages, cryopreserved and recovered successfully. We found no reduction
in cell viability after short term (<6 months) storage at −80 °C. Mitotic metaphase chromosomes were harvested from these
cell lines and used in differential staining, banding and fluorescent in situ hybridisation. Cell lines maintained normal
diploidy in all species. This study reports a simple non-invasive method for establishing primary cell lines from Australian
dragon lizards without sacrifice. The method is likely to be applicable to a range of species. Such cell lines provide a virtually
unlimited source of material for cytogenetic, evolutionary and genomic studies. 相似文献
943.
A procedure is presented for refinement of a homology model of E. coli tRNAVal, originally based on the X-ray structure of yeast tRNAPhe, using experimental residual dipolar coupling (RDC) and small angle X-ray scattering (SAXS) data. A spherical sampling algorithm
is described for refinement against SAXS data that does not require a globbic approximation, which is particularly important
for nucleic acids where such approximations are less appropriate. Substantially higher speed of the algorithm also makes its
application favorable for proteins. In addition to the SAXS data, the structure refinement employed a sparse set of NMR data
consisting of 24 imino N–HN RDCs measured with Pf1 phage alignment, and 20 imino N–HN RDCs obtained from magnetic field dependent alignment of tRNAVal. The refinement strategy aims to largely retain the local geometry of the 58% identical tRNAPhe by ensuring that the atomic coordinates for short, overlapping segments of the ribose-phosphate backbone and the conserved
base pairs remain close to those of the starting model. Local coordinate restraints are enforced using the non-crystallographic
symmetry (NCS) term in the XPLOR-NIH or CNS software package, while still permitting modest movements of adjacent segments.
The RDCs mainly drive the relative orientation of the helical arms, whereas the SAXS restraints ensure an overall molecular
shape compatible with experimental scattering data. The resulting structure exhibits good cross-validation statistics (jack-knifed
Q
free = 14% for the Pf1 RDCs, compared to 25% for the starting model) and exhibits a larger angle between the two helical arms
than observed in the X-ray structure of tRNAPhe, in agreement with previous NMR-based tRNAVal models.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
944.
Effects of seven potential probiotic strains on specific immune responses in healthy adults: a double-blind, randomized, controlled trial 总被引:1,自引:0,他引:1
Paineau D Carcano D Leyer G Darquy S Alyanakian MA Simoneau G Bergmann JF Brassart D Bornet F Ouwehand AC 《FEMS immunology and medical microbiology》2008,53(1):107-113
This pilot study investigated the immunomodulatory properties of seven probiotic strains. Eighty-three healthy volunteers aged 18-62 years consumed 2 x 10(10) CFU of bacteria or a placebo (maltodextrin) over 3 weeks (D0-D21). Subjects received an oral cholera vaccine at D7 and at D14; blood and saliva samples were collected at D0, D21 and D28. Serum samples were analyzed for specific IgA, IgG and IgM, and saliva samples were analyzed for specific IgA only, by ELISA. Statistical analyses were based on Wilcoxon's signed-rank test (intragroup analyses) and exact median t-test (intergroup analyses). Salivary analysis showed no difference in specific IgA concentrations between groups. Serum analysis indicated an effect of some of the tested strains on specific humoral responses. Between D0 and D21, IgG increased in two probiotic groups, for example, Bifidobacterium lactis Bl-04 and Lactobacillus acidophilus La-14, compared with controls (P=0.01). Trends toward significant changes in immunoglobulin serum concentrations compared with controls (P<0.1) were found for six out of the seven probiotic strains. In conclusion, some strains of probiotics demonstrated a faster immune response measured with serum immunoglobulin indicators, especially IgG, although overall vaccination was not influenced. Specific strains of probiotics may thus act as adjuvants to the humoral immune response following oral vaccination. 相似文献
945.
Ouwehand AC Bergsma N Parhiala R Lahtinen S Gueimonde M Finne-Soveri H Strandberg T Pitkälä K Salminen S 《FEMS immunology and medical microbiology》2008,53(1):18-25
Faecal and serum samples were collected over a period of 6 months from 55 institutionalized elderly subjects, who were enrolled in a double-blind placebo-controlled study. Participants were randomized in one of the three treatment groups: intervention (two probiotic Bifidobacterium longum strains: 2C and 46), placebo and commercial control (Bifidobacterium lactis Bb-12). The faecal Bifidobacterium microbiota was characterized by genus and species-specific PCR. Serum levels of the cytokines IL-10, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1 were determined by enzyme-linked immunosorbent assay. Each participant harboured on average approximately three different bifidobacterial species. The most frequently detected species were B. longum, Bifidobacterium adolescentis and Bifidobacterium bifidum. Depending on the treatment, the intervention resulted in specific changes in the levels of certain Bifidobacterium species, and positive correlations were found between the different species. Negative correlations were observed between the levels of Bifidobacterium species and the pro-inflammatory cytokine TNF-alpha and the regulatory cytokine IL-10. The presence of faecal B. longum and Bifidobacterium animalis correlated with reduced serum IL-10. The anti-inflammatory TGF-beta1 levels were increased over time in all three groups, and the presence of Bifidobacterium breve correlated with higher serum TGF-beta1 levels. This indicates that modulation of the faecal Bifidobacterium microbiota may provide a means of influencing inflammatory responses. 相似文献
946.
The polyadenylation factor subunit "Factor Interacting with Poly(A) polymerase" (Fip1) is an important bridging subunit in the eukaryotic polyadenylation complex. To better understand the functioning of Fip1 in Arabidopsis, a random combinatorial screen for peptides that interact with a conserved plant-specific domain in the protein was conducted. A search of the Arabidopsis proteome using these Fip1-binding peptides as queries resulted in the identification of a number of putative Fip1-interacting proteins. One of these was the polyadenylation factor subunit, CstF77. This purported interaction was confirmed by yeast two-hybrid and in vitro assays. Mutation of the motif identified in the phage display screen eliminated the interaction, corroborating the results of the phage display screen. The domain of CstF77 that interacts with Fip1 lies at its extreme C-terminus and is distinct from the part of CstF77 that binds CstF64. Taken together, these results suggest that Fip1 is situated near CstF64 in the polyadenylation complex. 相似文献
947.
948.
Adaptive responses by mouse early embryos to maternal diet protect fetal growth but predispose to adult onset disease 总被引:1,自引:0,他引:1
Watkins AJ Ursell E Panton R Papenbrock T Hollis L Cunningham C Wilkins A Perry VH Sheth B Kwong WY Eckert JJ Wild AE Hanson MA Osmond C Fleming TP 《Biology of reproduction》2008,78(2):299-306
Poor maternal nutrition during pregnancy can alter postnatal phenotype and increase susceptibility to adult cardiovascular and metabolic diseases. However, underlying mechanisms are largely unknown. Here, we show that maternal low protein diet (LPD), fed exclusively during mouse preimplantation development, leads to offspring with increased weight from birth, sustained hypertension, and abnormal anxiety-related behavior, especially in females. These adverse outcomes were interrelated with increased perinatal weight being predictive of later adult overweight and hypertension. Embryo transfer experiments revealed that the increase in perinatal weight was induced within blastocysts responding to preimplantation LPD, independent of subsequent maternal environment during later pregnancy. We further identified the embryo-derived visceral yolk sac endoderm (VYSE) as one mediator of this response. VYSE contributes to fetal growth through endocytosis of maternal proteins, mainly via the multiligand megalin (LRP2) receptor and supply of liberated amino acids. Thus, LPD maintained throughout gestation stimulated VYSE nutrient transport capacity and megalin expression in late pregnancy, with enhanced megalin expression evident even when LPD was limited to the preimplantation period. Our results demonstrate that in a nutrient-restricted environment, the preimplantation embryo activates physiological mechanisms of developmental plasticity to stablize conceptus growth and enhance postnatal fitness. However, activation of such responses may also lead to adult excess growth and cardiovascular and behavioral diseases. 相似文献
949.
Inhibitors of c-Jun N-terminal kinases: JuNK no more? 总被引:3,自引:0,他引:3
The c-Jun N-terminal kinases (JNKs) have been the subject of intense interest since their discovery in the early 1990s. Major research programs have been directed to the screening and/or design of JNK-selective inhibitors and testing their potential as drugs. We begin this review by considering the first commercially-available JNK ATP-competitive inhibitor, SP600125. We focus on recent studies that have evaluated the actions of SP600125 in lung, brain, kidney and liver following exposure to a range of stress insults including ischemia/reperfusion. In many but not all cases, SP600125 administration has proved beneficial. JNK activation can also follow infection, and we next consider recent examples that demonstrate the benefits of SP600125 administration in viral infection. Additional ATP-competitive JNK inhibitors have now been described following high throughput screening of small molecule libraries, but information on their use in biological systems remains limited and thus these inhibitors will require further evaluation. Peptide substrate-competitive ATP-non-competitive inhibitors of JNK have also now been described, and we discuss the recent advances in the use of JNK inhibitory peptides in the treatment of neuronal death, diabetes and viral infection. We conclude by raising a number of questions that should be considered in the quest for JNK-specific inhibitors. 相似文献
950.