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31.
Cook SA Akeson EC Calvano C Johnson KR Mandell J Hawes NL Bronson RT Roderick TH Davisson MT 《Cytogenetics and cell genetics》2001,93(1-2):77-82
The paracentric inversion In(3)55Rk on mouse Chromosome 3 (Chr 3) was induced by cesium irradiation. Genetic crosses indicate the proximal breakpoint cosegregates with D3Mit324 and D3Mit92; the distal breakpoint cosegregates with D3Mit127, D3Mit160, and D3Mit200. Giemsa-banded chromosomes show the inversion spans approximately 80% of Chr 3. The proximal breakpoint occurs within band 3A2, not 3B as reported previously; the distal breakpoint occurs within band 3H3. Mice homozygous for the inversion exhibit nephropathy indicative of uricase deficiency. Southern blot analyses of urate oxidase, Uox, show two RFLPs of genomic mutant DNA: an EcoRI site between exons 4-8 and a BamHI site 3' to exon 6. Mutant cDNA fails to amplify downstream of base 844 at the 3' end of exon 7. FISH analysis of chromosomes from inversion heterozygotes, using a cosmid clone containing genomic wild-type DNA for Uox exons 2-4, shows that a 5' segment of the mutated Uox allele on the inverted chromosome has been transposed from the distal breakpoint region to the proximal breakpoint region. Clinical, histopathological, and Northern analyses indicate that our radiation-induced mutation, uox(In), is a putative null. 相似文献
32.
Mário C BarrosoJúnior Guilherme P Esteves Thiago P Nunes Lucia MG Silva Alvaro CD Faria Pedro L Melo 《Biomedical engineering online》2011,10(1):14
Introduction
A novel system that combines a compact mobile instrument and Internet communications is presented in this paper for remote evaluation of tremors. The system presents a high potential application in Parkinson's disease and connects to the Internet through a TCP/IP protocol. Tremor transduction is carried out by accelerometers, and the data processing, presentation and storage were obtained by a virtual instrument. The system supplies the peak frequency (fp), the amplitude (Afp) and power in this frequency (Pfp), the total power (Ptot), and the power in low (1-4 Hz) and high (4-7 Hz) frequencies (Plf and Phf, respectively). 相似文献33.
Saman Bowatte Paul CD Newton Shona Brock Phil Theobald Dongwen Luo 《The ISME journal》2015,9(1):265-267
Nitrous oxide (N2O) emissions from grazed pastures are a product of microbial transformations of nitrogen and the prevailing view is that these only occur in the soil. Here we show this is not the case. We have found ammonia-oxidising bacteria (AOB) are present on plant leaves where they produce N2O just as in soil. AOB (Nitrosospira sp. predominantly) on the pasture grass Lolium perenne converted 0.02–0.42% (mean 0.12%) of the oxidised ammonia to N2O. As we have found AOB to be ubiquitous on grasses sampled from urine patches, we propose a ‘plant'' source of N2O may be a feature of grazed grassland.In terms of climate forcing, nitrous oxide (N2O) is the third most important greenhouse gas (Blunden and Arndt, 2013). Agriculture is the largest source of anthropogenic N2O (Reay et al., 2012) with about 20% of agricultural emissions coming from grassland grazed by animals (Oenema et al., 2005).Grazed grassland is a major source of N2O because grazers harvest nitrogen (N) from plants across a wide area but recycle it back onto the pasture, largely as urine, in patches of very high N concentration. The N in urine patches is often in excess of what can be used by plants resulting in losses through leaching as nitrate, as N2O and through volatilisation as ammonia (NH3) creating a high NH3 environment in the soil and plant canopy; an important point that we will return to later. The established wisdom is that N2O is generated exclusively by soil-based microbes such as ammonia-oxidising bacteria (AOB). This soil biology is represented in models designed to simulate N2O emissions and the soil is a target for mitigation strategies such as the use of nitrification inhibitors.We have previously shown that pasture plants can emit N2O largely through acting as a conduit for emissions generated in the soil, which are themselves controlled to some degree by the plant (Bowatte et al., 2014). In this case the origin of the emission is still the soil microbes. However, AOB have been found on the leaves of plants, for example, Norway spruce (Papen et al., 2002; Teuber et al., 2007) and weeds in rice paddies (Bowatte et al., 2006), prompting us to ask whether AOB might be present on the leaves of pasture species and contribute to N2O emissions as they do in soil.We looked for AOB on plants in situations where NH3 concentrations were likely to be high, choosing plants from urine patches in grazed pastures and plants from pastures surrounding a urea fertiliser manufacturing plant. DNA was extracted from the leaves (including both the surface and apoplast) and the presence of AOB tested using PCR. AOB were present in all the species we examined—the grasses Lolium perenne, Dactylis glomerata, Anthoxanthum odoratum, Poa pratensis, Bromus wildenowii and legumes Trifolium repens and T. subterraneum.To measure whether leaf AOB produce N2O, we used intact plants of ryegrass (L. perenne) lifted as cores from a paddock that had been recently grazed by adult sheep. The cores were installed in a chamber system designed to allow sampling of above- and belowground environments separately (Bowatte et al., 2014). N2O emissions were measured from untreated (control) plants and from plants where NH3 was added to the aboveground chamber and leaves were either untreated or sterilised by wiping twice with paper towels soaked in 1% hypoclorite (Sturz et al., 1997) and then with sterile water. We tested for the presence and abundance of AOB on the leaves by extracting DNA and using PCR and real-time PCR targeting the ammonia monoxygenase A (amoA) gene, which is characteristic of AOB. AOB identity was established using cloning and DNA sequencing. Further details of these experiments can be found in the Supplementary Information.The addition of NH3 to untreated plants significantly stimulated N2O emissions (P<0.001) compared with the controls; by contrast, the plants with sterilised leaves produced significantly less N2O than controls (P<0.001) even with NH3 added (Figure 1) providing strong evidence for emissions being associated with bacteria on the leaves. Control plants did emit N2O suggesting there was either sufficient NH3 available for bacterially generated emissions and/or other plant-based mechanisms were involved (Bowatte et al., 2014).Open in a separate windowFigure 1Effect of an elevated NH3 atmosphere and surface sterilisation of leaves on leaf N2O emissions measured over 1-h periods on three occasions during the day. Values are means (s.e.m.), where n=7.The major AOB species identified was Nitrosospira strain III7 that has been previously shown to produce N2O (Jiang and Bakken, 1999). We measured 109 AOB cells per m2 ryegrass leaf, assuming a specific leaf area of 250 cm2 g−1 leaf.The rate of production of N2O (0.1–0.17 mg N2O-N per m2 leaf area per hour) can be translated to a field situation using the leaf area index (LAI)—1 m2 leaf per m2 ground would be an LAI of 1. LAI in a pasture can vary from <1 to >6 depending on the management (for example, Orr et al., 1988). At LAI of 1, the AOB leaf emission rate would equate to a N2O emission rate of about 0.1–0.3 mg N2O-N per m2 ground per hour. By comparison, the emission rates measured after dairy cattle urine (650 kg N ha−1) was applied to freely and poorly drained soil were 0.024–1.55 and 0.048–3.33 mg N2O-N per m2 ground per hour, respectively (Li and Kelliher, 2005).The fraction of the NH3 that was converted to N2O by the leaf AOB was 0.02–0.42% (mean 0.12%). The mean value is close to that measured for Nitrosospira strains including strain III7 isolated from acidic, loamy and sandy soils where values ranged from 0.07 to 0.10% (Jiang and Bakken, 1999). This is good evidence that the AOB on leaves have the capacity to produce N2O at the same rate as AOB in soils. We do not suggest that leaf AOB will produce as much N2O as soil microbes; however, because leaf AOB have access to a source of substrate—volatilised NH3—that is unavailable to soil microbes and may constitute 26% (Laubach et al., 2013) to 40% (Carran et al., 1982) of the N deposited in the urine, N2O emissions from these aboveground AOB are additional to soil emissions. Further research is required to identify the situations in which leaf AOB contribute to total emissions and to quantify this contribution. 相似文献
34.
35.
Kumaran Kandasamy Sujatha S Mohan Rajesh Raju Shivakumar Keerthikumar Ghantasala S Sameer Kumar Abhilash K Venugopal Deepthi Telikicherla Daniel J Navarro Suresh Mathivanan Christian Pecquet Sashi Kanth Gollapudi Sudhir Gopal Tattikota Shyam Mohan Hariprasad Padhukasahasram Yashwanth Subbannayya Renu Goel Harrys KC Jacob Jun Zhong Raja Sekhar Vishalakshi Nanjappa Lavanya Balakrishnan Roopashree Subbaiah YL Ramachandra Abdul B Rahiman Keshava TS Prasad Jian-Xin Lin Jon CD Houtman Stephen Desiderio Jean-Christophe Renauld Stefan N Constantinescu Osamu Ohara Toshio Hirano Masato Kubo Sujay Singh Purvesh Khatri Sorin Draghici Gary D Bader Chris Sander Warren J Leonard Akhilesh Pandey 《Genome biology》2010,11(1):1-9
36.
Protein glycosylation is a common post-translational modification that is involved in many biological processes, including cell adhesion, protein-protein and receptor-ligand interactions. The glycoproteome constitutes a source for identification of disease biomarkers since altered protein glycosylation profiles are associated with certain human ailments. Glycoprotein analysis by mass spectrometry of biological samples, such as blood serum, is hampered by sample complexity and the low concentration of the potentially informative glycopeptides and -proteins. We assessed the utility of lectin-based and HILIC-based affinity enrichment techniques, alone or in combination, for preparation of glycoproteins and glycopeptides for subsequent analysis by MALDI and ESI mass spectrometry. The methods were successfully applied to human serum samples and a total of 86 N-glycosylation sites in 45 proteins were identified using a mixture of three immobilized lectins for consecutive glycoprotein enrichment and glycopeptide enrichment. The combination of lectin affinity enrichment of glycoproteins and subsequent HILIC enrichment of tryptic glycopeptides identified 81 N-glycosylation sites in 44 proteins. A total of 63 glycosylation sites in 38 proteins were identified by both methods, demonstrating distinct differences and complementarity. Serial application of custom-made microcolumns of mixed, immobilized lectins proved efficient for recovery and analysis of glycopeptides from serum samples of breast cancer patients and healthy individuals to assess glycosylation site frequencies. 相似文献
37.
De AK Miller-Graziano CL Calvano SE Laudanski K Lowry SF Moldawer LL Remick DG Rajicic N Schoenfeld D Tompkins RG 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(9):6155-6162
Although activation of human innate immunity after endotoxin administration is well established, in vivo endotoxin effects on human T cell responses are not well understood. Most naive human T cells do not express receptors for LPS, but can respond to endotoxin-induced mediators such as chemokines. In this study, we characterized the in vivo response of peripheral human T cell subsets to endotoxin infusion by assessing alterations in isolated T cells expressing different phenotypes, intracellular cytokines, and systemic chemokines concentration, which may influence these indirect T cell responses. Endotoxin administration to healthy subjects produced T cell activation as confirmed by a 20% increase in intracellular IL-2, as well as increased CD28 and IL-2R alpha-chain (CD25) expression. Endotoxin induced indirect activation of T cells was highly selective among the T cell subpopulations. Increased IL-2 production (36.0 +/- 3.7 to 53.2 +/- 4.1) vs decreased IFN-gamma production (33.8 +/- 4.2 to 19.1 +/- 3.2) indicated selective Th1 activation. Th2 produced IL-13 was minimally increased. Differentially altered chemokine receptor expression also indicated selective T cell subset activation and migration. CXCR3+ and CCR5+ expressing Th1 cells were decreased (CXCR3 44.6 +/- 3.2 to 33.3 +/- 4.6 and CCR5 24.8 +/- 2.3 to 12 +/- 1.4), whereas plasma levels of their chemokine ligands IFN-gamma-inducible protein 10 and MIP-1alpha were increased (61.4 +/- 13.9 to 1103.7 +/- 274.5 and 22.8 +/- 6.2 to 55.7 +/- 9.5, respectively). In contrast, CCR4+ and CCR3 (Th2) proportions increased or remained unchanged whereas their ligands, eotaxin and the thymus and activation-regulated chemokine TARC, were unchanged. The data indicate selective activation among Th1 subpopulations, as well as differential Th1/Th2 activation, which is consistent with a selective induction of Th1 and Th2 chemokine ligands. 相似文献
38.
39.
Microbial diversity and complexity in hypersaline environments: A preliminary assessment 总被引:4,自引:0,他引:4
The microbial communities in solar salterns and a soda lake have been characterized using two techniques: BIOLOG, to estimate
the metabolic potential, and amplicon length heterogeneity analysis, to estimate the molecular diversity of these communities.
Both techniques demonstrated that the halophilic Bacteria and halophilic Archaea populations in the Eilat, Israel saltern
are dynamic communities with extensive metabolic potentials and changing community structures. Halophilic Bacteria were detected
in Mono Lake and the lower salinity ponds at the Shark Bay saltern in Western Australia, except when the crystallizer samples
were stressed by exposure to Acid Green Dye #9899. At Shark Bay, halophilic Archaea were found only in the crystallizer samples.
These data confirm both the metabolic diversity and the phylogenetic complexity of the microbial communities and assert the
need to develop more versatile media for the cultivation of the diversity of bacteria in hypersaline environments. Journal of Industrial Microbiology & Biotechnology (2002) 28, 48–55 DOI: 10.1038/sj/jim/7000175
Received 20 May 2001/ Accepted in revised form 15 June 2001 相似文献
40.
Maria Julia Calonge Marga Nadal Savino Calvano Xavier Testar Leopoldo Zelante Antonio Zorzano Xavier Estivill Paolo Gasparini Manuel Palacín Virginia Nunes 《Human genetics》1995,95(6):633-636
We have established rBAT (named as SLC3A1 in the Genome Data Base) as a gene responsible for cystinuria, a heritable disorder of amino acid transport. The cystinuria locus has been mapped by linkage between microsatellite markers D2S119 and D2S177. Fluorescene in situ hybridization (FISH) either with Alu-polymerasechain-reaction (PCR)-amplified sequences of a yeast artificial chromosome (YAC) containing the rBAT gene or with rBAT-specific PCR-amplified genomic fragments, and chromosome G-banding have cytogenetically mapped rBAT to 2p16.3. In order to correlate the physical and genetic information on cystinuria, we have performed FISH with combinations of Alu-PCR- amplified sequences from YACs containing rBAT or the D2S119 and D2S177 loci. In all cases, a fused signal is obtained that demonstrates their close physical location; this allows the assignment of rBAT, cystinuria and their linked markers, D2S119 and D2S177, to 2p16. 相似文献