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71.
Appaix F Girod S Boisseau S Römer J Vial JC Albrieux M Maurin M Depaulis A Guillemain I van der Sanden B 《PloS one》2012,7(4):e35169
Fluorescent staining of astrocytes without damaging or interfering with normal brain functions is essential for intravital microscopy studies. Current methods involved either transgenic mice or local intracerebral injection of sulforhodamine 101. Transgenic rat models rarely exist, and in mice, a backcross with GFAP transgenic mice may be difficult. Local injections of fluorescent dyes are invasive. Here, we propose a non-invasive, specific and ubiquitous method to stain astrocytes in vivo. This method is based on iv injection of sulforhodamine dyes and is applicable on rats and mice from postnatal age to adulthood. The astrocytes staining obtained after iv injection was maintained for nearly half a day and showed no adverse reaction on astrocytic calcium signals or electroencephalographic recordings in vivo. The high contrast of the staining facilitates the image processing and allows to quantify 3D morphological parameters of the astrocytes and to characterize their network. Our method may become a reference for in vivo staining of the whole astrocytes population in animal models of neurological disorders. 相似文献
72.
Development and characterization of highly polymorphic long TC repeat microsatellite markers for genetic analysis of peanut 总被引:4,自引:0,他引:4
Selma E Macedo Márcio C Moretzsohn Soraya C M Leal-Bertioli Dione MT Alves Ediene G Gouvea Vania CR Azevedo David J Bertioli 《BMC research notes》2012,5(1):1-10
Background
The immune system has paradoxical roles during cancer development and the prognostic significance of immune modulating factors is controversial. The aim of this study was to determine the expression of cyclooxygenase 2 (COX-2), transforming growth factor-beta (TGF- beta), interleukin-10 (IL-10) and their prognostic significance in breast cancers. Ki67 was included as a measure of growth fraction of tumor cells.Methods
On immunohistochemical stained slides from 38 breast cancer patients, we performed digital video analysis of tumor cell areas and adjacent tumor stromal areas from the primary tumors and their corresponding lymph node metastases. COX-2 was recorded as graded staining intensity.Results
The expression of TGF-beta, IL-10 and Ki67 were recorded in tumor cell areas and adjacent tumor stromal areas. In both primary tumors and metastases, the expression of COX-2 was higher in the tumor stromal areas than in the tumor cell areas (both P < 0.001). High stromal staining intensity in the primary tumors was associated with a 3.9 (95% CI 1.1-14.2) times higher risk of death compared to the low staining group (P = 0.036). The expression of TGF-beta was highest in the tumor cell areas of both primary tumors and metastases (both P < 0.001). High stromal expression of TGF-beta was associated with increased mortality. For IL-10, the stromal expression was highest in the primary tumors (P < 0.001), whereas in the metastases the expression was highest in tumor cell areas (P < 0.001). High IL-10 expression in tumor- and stromal cell areas of primary tumors predicted mortality. Ki67 was higher expressed in tumor stromal areas of the metastases, and in tumor cell areas of the primary tumors (P < 0.001). Ki67 expression in tumor cell areas and stromal areas of the metastases was independently associated with breast cancer mortality.Conclusions
Stromal expression of COX-2, TGF-beta and Ki67 may facilitate tumor progression in breast cancer. 相似文献73.
Comprehensive definition of genome features in Spirodela polyrhiza by high‐depth physical mapping and short‐read DNA sequencing strategies 下载免费PDF全文
Todd P. Michael Douglas Bryant Ryan Gutierrez Nikolai Borisjuk Philomena Chu Hanzhong Zhang Jing Xia Junfei Zhou Hai Peng Moaine El Baidouri Boudewijn ten Hallers Alex R. Hastie Tiffany Liang Kenneth Acosta Sarah Gilbert Connor McEntee Scott A. Jackson Todd C. Mockler Weixiong Zhang Eric Lam 《The Plant journal : for cell and molecular biology》2017,89(3):617-635
Spirodela polyrhiza is a fast‐growing aquatic monocot with highly reduced morphology, genome size and number of protein‐coding genes. Considering these biological features of Spirodela and its basal position in the monocot lineage, understanding its genome architecture could shed light on plant adaptation and genome evolution. Like many draft genomes, however, the 158‐Mb Spirodela genome sequence has not been resolved to chromosomes, and important genome characteristics have not been defined. Here we deployed rapid genome‐wide physical maps combined with high‐coverage short‐read sequencing to resolve the 20 chromosomes of Spirodela and to empirically delineate its genome features. Our data revealed a dramatic reduction in the number of the rDNA repeat units in Spirodela to fewer than 100, which is even fewer than that reported for yeast. Consistent with its unique phylogenetic position, small RNA sequencing revealed 29 Spirodela‐specific microRNA, with only two being shared with Elaeis guineensis (oil palm) and Musa balbisiana (banana). Combining DNA methylation data and small RNA sequencing enabled the accurate prediction of 20.5% long terminal repeats (LTRs) that doubled the previous estimate, and revealed a high Solo:Intact LTR ratio of 8.2. Interestingly, we found that Spirodela has the lowest global DNA methylation levels (9%) of any plant species tested. Taken together our results reveal a genome that has undergone reduction, likely through eliminating non‐essential protein coding genes, rDNA and LTRs. In addition to delineating the genome features of this unique plant, the methodologies described and large‐scale genome resources from this work will enable future evolutionary and functional studies of this basal monocot family. 相似文献
74.
Peter Doig Boudewijn L. de Jonge Richard A. Alm Eric D. Brown Maria Uria-Nickelsen Brian Noonan Scott D. Mills Peter Tummino Gilles Carmel Braydon C. Guild Donald T. Moir Gerald F. Vovis Trevor J. Trust 《Microbiological reviews》1999,63(3):675-707
Helicobacter pylori is a gram-negative bacteria which colonizes the gastric mucosa of humans and is implicated in a wide range of gastroduodenal diseases. This paper reviews the physiology of this bacterium as predicted from the sequenced genomes of two unrelated strains and reconciles these predictions with the literature. In general, the predicted capabilities are in good agreement with reported experimental observations. H. pylori is limited in carbohydrate utilization and will use amino acids, for which it has transporter systems, as sources of carbon. Energy can be generated by fermentation, and the bacterium possesses components necessary for both aerobic and anaerobic respiration. Sulfur metabolism is limited, whereas nitrogen metabolism is extensive. There is active uptake of DNA via transformation and ample restriction-modification activities. The cell contains numerous outer membrane proteins, some of which are porins or involved in iron uptake. Some of these outer membrane proteins and the lipopolysaccharide may be regulated by a slipped-strand repair mechanism which probably results in phase variation and plays a role in colonization. In contrast to a commonly held belief that H. pylori is a very diverse species, few differences were predicted in the physiology of these two unrelated strains, indicating that host and environmental factors probably play a significant role in the outocme of H. pylori-related disease. 相似文献
75.
In previous studies, Laminaria saccharina L. (Lamour.) sporophytes were found to exhibit two major peaks of sporogenesis and an annual life cycle in Long Island Sound, New York. Young sporophytes were observed shortly after the sporogenesis peaks in early autumn and spring, but most of the mature sporophytes decayed during summer. A new study was conducted to determine if the spring sporogenesis activity contributed to the recruitment observed in autumn through oversummering of gametophytic and juvenile sporophytic stages, as previously suggested. Reproduction and growth in gametophytes and growth in juvenile sporophytes were studied under crossed gradients of light and temperature. Periodic outplantings of substrata seeded with gametophytic and sporophytic stages to the field were conducted to assess actual survival. The optimum temperature and light conditions for gametophyte development, growth and reproduction varied with the time of year meiospores were obtained. Most of this variation was attributable to temperature. A seasonal adaptation to temperature in most developmental stages was observed. Higher temperatures resulted in greater numbers of male gametophytes. Gametophytic stages could develop at all times, suggesting that oversummering in this stage was possible. Juvenile sporophytes had a narrower optimum temperature range and again photon fluence rate contributed little to observed variances. Out planting of sporophytic stages at various times during the year indicated only sporophytes prepared from autumn and winter could survive summer conditions. The thalli of these plants grew rapidly in spring and eroded back to the meristematic region in summer. Most of these plants then quickly became reproductive, resulting in another autumn sporogenesis peak. Gametophytic and sporophytic outplantings prepared from spring meiospores did not survive the summer. Thus, the recruitment observed in autumn can only be the result of the previous autumn's sporogenesis activity. The sporogenous activities of spring and early summer appear to be unimportant, despite the fact that all reproductive indices are superior at those times. 相似文献
76.
Ribosomal RNA secondary structure: compensatory mutations and implications for phylogenetic analysis 总被引:6,自引:0,他引:6
Using sequence data from the 28S ribosomal RNA (rRNA) genes of selected
vertebrates, we investigated the effects that constraints imposed by
secondary structure have on the phylogenetic analysis of rRNA sequence
data. Our analysis indicates that characters from both base-pairing regions
(stems) and non-base-pairing regions (loops) contain phylogenetic
information, as judged by the level of support of the phylogenetic results
compared with a well-established tree based on both morphological and
molecular data. The best results (the greatest level of support of
well-accepted nodes) were obtained when the complete data set was used.
However, some previously supported nodes were resolved using either the
stem or loop bases alone. Stem bases sustain a greater number of
compensatory mutations than would be expected at random, but the number is
< 40% of that expected under a hypothesis of perfect compensation to
maintain secondary structure. Therefore, we suggest that in phylogenetic
analyses, the weighting of stem characters be reduced by no more than 20%,
relative to that of loop characters. In contrast to previous suggestions,
we do not recommend weighting of stem positions by one-half, compared with
that of loop positions, because this overcompensates for the constraints
that selection imposes on the secondary structure of rRNA.
相似文献
77.
Boudewijn D. Meesschaert Jesús Cortés Emilio Alvarez Paloma Liras Juan F. Martín 《Biotechnology Techniques》1987,1(2):137-140
Summary An improved HPLC method is described to separate isopenicillin N from its penicilloic acid and from the reduced and oxidized forms of -(L--amino-adipyl)-L-cysteinyl-D-valine and of DTT. When applied to assay the activity of isopenicillin N synthase only isopenicillin N and its penicilloic acid could be detected. 相似文献
78.
Boudewijn Catry Siska Croubels Stefan Schwarz Piet Deprez Bianca Cox Corinna Kehrenberg Geert Opsomer Annemie Decostere Freddy Haesebrouck 《Acta veterinaria Scandinavica》2008,50(1):36
The influence of enrofloxacin administration (5 mg/kg) for five consecutive days on the occurrence of Pasteurella multocida in the upper respiratory tract of two healthy calves was monitored over a 10-day period. From nasal swabs of two additional
healthy control calves, which received a placebo saline administration, P. multocida was isolated throughout the study period. In the enrofloxacin treated calves, P. multocida was not demonstrated in the nasopharynx from 48 h after the first injection until two days after the last administration,
when P. multocida reappeared and proved to be clonal in nature to the original isolates. During the experiment, no change in minimal inhibitory
concentration for enrofloxacin of the P. multocida isolates was detected (MIC ≤ 0.015 μg/mL). Enrofloxacin concentrations were determined in the plasma by a high-performance
liquid chromatography method with fluorescence detection. The PK/PD indices AUC/MIC and Cmax/MIC ratio were calculated and found to be 1157.7 and 129.8, respectively. Remarkably, the respiratory pathogen Arcanobacterium pyogenes became the predominant recovered organism in the nasopharynx of one animal following enrofloxacin therapy throughout the
remaining of the experiment. 相似文献
79.
80.
Henk Talma Yvonne Sch?nbeck Paula van Dommelen Boudewijn Bakker Stef van Buuren Remy A. HiraSing 《PloS one》2013,8(4)