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61.
M.D. Mitchell J.G. Bibby B.R. Hicks A.C. Turnbull 《Prostaglandins & other lipid mediators》1978,16(6):931-937
Human amnion, chorion, decidua and placenta produced 6-oxo-PGF1α when superfused
. Furthermore amnion, an avascular tissue, produced more 6-oxo-PGF1α after labour than all other tissues investigated and its production of 6-oxo-PGF1α was significantly greater after labour than before the onset of labour. These findings suggest that prostacyclin production by foetal membranes may have a role in the mechanisms controlling human parturition. Moreover, this is the first evidence for the production of prostacyclin by an avascular tissue. 相似文献
62.
The petroleum industry has an increasing interest in understanding the microbial communities driving biofouling and biocorrosion in reservoirs, wells, and infrastructure. However, sampling of the relevant produced fluids from subsurface environments for microbiological analyses is often challenged by high liquid pressures, workplace regulations, operator liability concerns, and remote sampling locations. These challenges result in infrequent sampling opportunities and the need to store and preserve the collected samples for several days or weeks. Maintaining a representative microbial community structure from produced fluid samples throughout storage and handling is essential for accurate results of downstream microbial analyses. Currently, no sample handling or storage recommendations exist for microbiological analyses of produced fluid samples. We used 16S rRNA gene sequencing to monitor the changes in microbial communities in hypersaline produced water stored at room temperature or at 4?°C for up to 7 days. We also analyzed storage at ?80?°C across a 3-week period. The results suggest ideal handling methods would include placing the collected sample on ice as soon as possible, but at least within 24?h, followed by shipping the samples on ice over 2–3?days, and finally, long-term storage in the ?20?°C or ?80?°C freezer. 相似文献
63.
Eduardo AVF Ramalho Jo?o LQ Silva-Filho Marina FS Cartaxo Carmelita BL Cavalcanti Moacyr JBM Rêgo Maria BM Oliveira Eduardo IC Beltr?o 《Biological research》2014,47(1)
Background
BRCA protein interacts with at least 13 different proteins that have been implicated with cancer susceptibility and loss of BRCA function is correlated to sensitivity to DNA crosslinking agents in preclinical models.Results
BRCA2 methylation frequency was 44%, p53 Pro22 allele frequency was 32% and heterozygous frequency of Arg/Pro72 genotype was 60% which could be associated as risk factor for metastasis (p = 0.046 OR = 4.190). Regarding to polymorphism of codon 249 the frequency of Arg249 allele presented 82% which was considered not statistically significant.Conclusions
There was not statistical significance to BRCA2 promoter methylation with any parameters chosen. However, our findings suggest that patients who present heterozygous genotype at codon 72 of p53 gene may have a major susceptibility to any type of metastasis and this could serve as potential auxiliary biomarker for poor prognosis. 相似文献64.
A 522-base-long Y-chromosomal sequence was isolated from a BALB/c genomic
library and was designated "BF046." It is repeated about 200 times in the
male genome, and a difference was detected between the Mus musculus
musculus and the M. m. domesticus type Y chromosomes. BF046- related
sequences were present over the entire length of the Y chromosome as
visualized by in situ hybridization. Southern blot analysis against DNAs
isolated from eight species in the genus Mus showed that BF046-related
sequences were amplified in the Y chromosomes of three closely related
species: M. musculus, M. spicilegus, and M. spretus. To gain insight into
the stability of the BF046 sequence family, we isolated 18 additional
clones from these three mouse species and compared their sequences. The M.
musculus sequences differed from the M. spicilegus and M. spretus sequences
by two indels. The remaining parts of the sequences were very similar, but
both parsimony and distance-based analytical methods divided the sequences
into the same four subgroups, with each species having its own subgroup(s).
Thus, the Y chromosomes of M. musculus, M. spicilegus, and M. spretus can
be distinguished from one another.
相似文献
65.
Thompson MJ Abdul-Rahman S Baker TG Rafferty JA Margison GP Bibby MC 《Journal of reproduction and fertility》2000,119(2):339-346
The O(6)-alkylguanine-DNA alkyltransferase inactivator O(6)-benzylguanine was administered to BALB/c mice either alone or before exposure to 1,3-bis(2-chloroethyl)-1-nitrosourea to study the role of the DNA repair protein O(6)-alkylguanine-DNA alkyltransferase in the protection of the testis against anti-cancer O(6)-alkylating agents. Exposure of the mice to 1, 3-bis(2-chloroethyl)-1-nitrosourea or O(6)-benzylguanine alone did not produce any marked testicular toxicity at the times studied. Testicular O(6)-alkylguanine-DNA alkyltransferase concentrations were assayed between 0 and 240 min after O(6)-benzylguanine treatment and were shown to be > 95% depleted 15 min after treatment with O(6)-benzylguanine and remained at > 95% at all the times assayed. Histological examination, the reduction in testicular mass and the induction of spermatogenic cell apoptosis showed that this depletion significantly potentiated 1, 3-bis(2-chloroethyl)-1-nitrosourea-induced testicular damage after treatment. Major histological damage was apparent 42 days after treatment, demonstrating that the stem spermatogonia were significantly affected by the combination. These results demonstrate that O(6)-alkylguanine-DNA alkyltransferase plays a significant role in protecting the spermatogenic cells from damage caused by DNA alkylation and indicate that the observed toxicity may result from damage to stem spermatogonia. 相似文献
66.
D Viuff P J Hendriksen P L Vos S J Dieleman B M Bibby T Greve P Hyttel P D Thomsen 《Biology of reproduction》2001,65(1):204-208
The frequency of chromosome abnormalities was investigated in cattle embryos (n = 256) derived from superovulated heifers (n = 35) on Days 2, 3, 4, and 5 postovulation (PO). Interphase nuclei (n = 4358) were analyzed for chromosome abnormalities using fluorescent in situ hybridization with chromosome 6- and chromosome 7-specific probes and the developmental rate was described by scoring cell numbers. We found that 93%, 85%, 84%, and 69% of the embryos from Days 2, 3, 4, and 5 PO, respectively, displayed a normal diploid chromosome number in all cells. Of the embryos containing abnormal cells, mixoploidy was significantly more frequent than polyploidy. The percentage of mixoploidy at Days 2, 3, 4, and 5 PO was 5%, 13%, 16%, and 31%, respectively, whereas the percentages of polyploidy were 2%, 2%, 0%, and 0%, respectively. The mean number of cells per embryo was 4.7, 8, 11.5, and 48.3, respectively, at Days 2, 3, 4, and 5 PO. Thus, in vivo-developed embryos were significantly more advanced than the in vitro-produced (IVP) embryos except for Day 2. In conclusion, a significantly lower frequency of chromosomally abnormal embryos, in particular displaying polyploidy early after fertilization, was seen in in vivo versus IVP embryos, and these chromosomal abnormalities may be inherent to the process of IVP in cattle. 相似文献
67.
The R-spondin protein family 总被引:1,自引:0,他引:1
The four vertebrate R-spondin proteins are secreted agonists of the canonical Wnt/β-catenin signaling pathway. These proteins are approximately 35 kDa, and are characterized by two amino-terminal furin-like repeats, which are necessary and sufficient for Wnt signal potentiation, and a thrombospondin domain situated more towards the carboxyl terminus that can bind matrix glycosaminoglycans and/or proteoglycans. Although R-spondins are unable to initiate Wnt signaling, they can potently enhance responses to low-dose Wnt proteins. In humans, rare disruptions of the gene encoding R-spondin1 cause a syndrome of XX sex reversal (phenotypic male), palmoplantar keratosis (a thickening of the palms and soles caused by excess keratin formation) and predisposition to squamous cell carcinoma of the skin. Mutations in the gene encoding R-spondin4 cause anonychia (absence or hypoplasia of nails on fingers and toes). Recently, leucine-rich repeat-containing G-protein-coupled receptor (Lgr)4, Lgr5 and Lgr6, three closely related orphans of the leucine-rich repeat family of G-protein-coupled receptors, have been identified as receptors for R-spondins. Lgr5 and Lgr6 are markers for adult stem cells. Because R-spondins are potent stimulators of adult stem cell proliferation in vivo and in vitro, these findings might guide the therapeutic use of R-spondins in regenerative medicine. 相似文献
68.
69.
Jeffery J. Newsome Mary Hassani Elizabeth Swann Jane M. Bibby Howard D. Beall Christopher J. Moody 《Bioorganic & medicinal chemistry》2013,21(11):2999-3009
A series of heterocyclic quinones based on benzofuran, benzothiophene, indazole and benzisoxazole has been synthesized, and evaluated for their ability to function as substrates for recombinant human NAD(P)H:quinone oxidoreductase (NQO1), a two-electron reductase upregulated in tumor cells. Overall, the quinones are excellent substrates for NQO1, approaching the reduction rates observed for menadione. 相似文献
70.
Christian Daugaard Peters Krista Dybtved Kjaergaard Jens Dam Jensen Kent Lodberg Christensen Charlotte Strandhave Ida Noerager Tietze Marija Kristina Novosel Bo Martin Bibby Bente Jespersen 《PloS one》2015,10(6)