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1.
Kotakonda Arunasri Mohammed Adil Katari Venu Charan Chatterjee Suvro Seerapu Himabindu Reddy Sisinthy Shivaji 《PloS one》2013,8(3)
This study demonstrates the effects of simulated microgravity on E. coli K 12 MG1655 grown on LB medium supplemented with glycerol. Global gene expression analysis indicated that the expressions of hundred genes were significantly altered in simulated microgravity conditions compared to that of normal gravity conditions. Under these conditions genes coding for adaptation to stress are up regulated (sufE and ssrA) and simultaneously genes coding for membrane transporters (ompC, exbB, actP, mgtA, cysW and nikB) and carbohydrate catabolic processes (ldcC, ptsA, rhaD and rhaS) are down regulated. The enhanced growth in simulated gravity conditions may be because of the adequate supply of energy/reducing equivalents and up regulation of genes involved in DNA replication (srmB) and repression of the genes encoding for nucleoside metabolism (dfp, pyrD and spoT). In addition, E. coli cultured in LB medium supplemented with glycerol (so as to protect the cells from freezing temperatures) do not exhibit multiple stress responses that are normally observed when cells are exposed to microgravity in LB medium without glycerol. 相似文献
2.
J?rg Lesting Thiemo Daldrup Venu Narayanan Christian Himpe Thomas Seidenbecher Hans-Christian Pape 《PloS one》2013,8(10)
Theta oscillations are considered crucial mechanisms in neuronal communication across brain areas, required for consolidation and retrieval of fear memories. One form of inhibitory learning allowing adaptive control of fear memory is extinction, a deficit of which leads to maladaptive fear expression potentially leading to anxiety disorders. Behavioral responses after extinction training are thought to reflect a balance of recall from extinction memory and initial fear memory traces. Therefore, we hypothesized that the initial fear memory circuits impact behavioral fear after extinction, and more specifically, that the dynamics of theta synchrony in these pathways signal the individual fear response. Simultaneous multi-channel local field and unit recordings were obtained from the infralimbic prefrontal cortex, the hippocampal CA1 and the lateral amygdala in mice. Data revealed that the pattern of theta coherence and directionality within and across regions correlated with individual behavioral responses. Upon conditioned freezing, units were phase-locked to synchronized theta oscillations in these pathways, characterizing states of fear memory retrieval. When the conditioned stimulus evoked no fear during extinction recall, theta interactions were directional with prefrontal cortical spike firing leading hippocampal and amygdalar theta oscillations. These results indicate that the directional dynamics of theta-entrained activity across these areas guide changes in appraisal of threatening stimuli during fear memory and extinction retrieval. Given that exposure therapy involves procedures and pathways similar to those during extinction of conditioned fear, one therapeutical extension might be useful that imposes artificial theta activity to prefrontal cortical-amygdalo-hippocampal pathways that mimics the directionality signaling successful extinction recall. 相似文献
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Kumudini Tota Nihar Rayabarapu Sowmya Moosa Venu Talla Balaji Bhyravbhatla Srinivasa Rao 《Bioinformation》2013,9(7):378-380
According to International Diabetes Federation (IDF), India has 62.4 million people with diabetes and by 2030 it is predicted that
the number will rise to 100 million. Studies claim that there are around 410 experimentally proven Indian medicinal plants which
have anti-diabetic activity, of which the mechanism of action of 109 plants has been elucidated or reported. So, the need of the hour
is to explore the claims of Indian medicinal flora and open up the facets of many Indian plants which are being examined for their
beneficial role in diabetes. So, we created a database (InDiaMed) of Indian medicinal plants that captures their role in anti-diabetic
activity. InDiaMed''s features include chemical, pharmacological, biochemical and geographical information of the medicinal plant,
scientifically relevant information of the plant, and the coherent research done on it in the field of diabetes. The database also
includes the list of poly-herbal formulations which are used for treatment of diabetes in India.
Availability
http://www.indiamed.info 相似文献5.
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Liu G Loraine AE Shigeta R Cline M Cheng J Valmeekam V Sun S Kulp D Siani-Rose MA 《Nucleic acids research》2003,31(1):82-86
NetAffx (http://www.affymetrix.com) details and annotates probesets on Affymetrix GeneChip microarrays. These annotations include (i) static information specific to the probeset composition; (ii) sequence annotations extracted from public databases; and (iii) protein sequence-level annotations derived from public domain programs, as well as libraries of hidden Markov models (HMMs) developed at Affymetrix. For each probeset, NetAffx lists the probe sequences, and the consensus sequence interrogated by the probes; for the larger chip sets, interactive maps display this sequence data in genomic context. Sequence annotations include Gene Ontology (GO) terms and depiction of GO graph relationships; predicted protein domains and motifs; orthologous sequences; links to relevant pathways; and links to public databases including UniGene, LocusLink, SWISS-PROT and OMIM. 相似文献
8.
Miller G Pillarisetty VG Shah AB Lahrs S Xing Z DeMatteo RP 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(6):2875-2885
GM-CSF is critical for dendritic cell (DC) survival and differentiation in vitro. To study its effect on DC development and function in vivo, we used a gene transfer vector to transiently overexpress GM-CSF in mice. We found that up to 24% of splenocytes became CD11c+ and the number of DC increased up to 260-fold to 3 x 10(8) cells. DC numbers remained substantially elevated even 75 days after treatment. The DC population was either CD8alpha+CD4- or CD8alpha-CD4- but not CD8alpha+CD4+ or CD8alpha-CD4+. This differs substantially from subsets recruited in normal or Flt3 ligand-treated mice or using GM-CSF protein injections. GM-CSF-recruited DC secreted extremely high levels of TNF-alpha compared with minimal amounts in DC from normal or Flt3 ligand-treated mice. Recruited DC also produced elevated levels of IL-6 but almost no IFN-gamma. GM-CSF DC had robust immune function compared with controls. They had an increased rate of Ag capture and caused greater allogeneic and Ag-specific T cell stimulation. Furthermore, GM-CSF-recruited DC increased NK cell lytic activity after coculture. The enhanced T cell and NK cell immunostimulation by GM-CSF DC was in part dependent on their secretion of TNF-alpha. Our findings show that GM-CSF can have an important role in DC development and recruitment in vivo and has potential application to immunotherapy in recruiting massive numbers of DC with enhanced ability to activate effector cells. 相似文献
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Non-invasive longitudinal detection and evaluation of gene expression in living animals can provide investigators with an understanding of the ontogeny of a gene's biological function(s). Currently, mouse model systems are used to optimize magnetic resonance imaging (MRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and optical imaging modalities to detect gene expression and protein function. These molecular imaging strategies are being developed to assess tumor growth and the tumor microenvironment. In addition, pre-labeling of progenitor cells can provide invaluable information about the developmental lineage of stem cells both in organogenesis and tumorigenesis. The feasibility of this approach has been extensively tested by targeting of endogenous tumor cell receptors with labeled ligand (or ligand analog) reporters and targeting enzymes with labeled substrate (or substrate analog). We will primarily discuss MRI, PET, and SPECT imaging of cell surface receptors and the feasibility of non-invasive imaging of gene expression using the tumor microenvironment (e.g., hypoxia) as a conditional regulator of gene expression. 相似文献
10.
Processing of viral envelope glycoprotein by the endomannosidase pathway: evaluation of host cell specificity 总被引:4,自引:2,他引:2
Endo-alpha-D-mannosidase is an enzyme involved in N-linked oligosaccharide
processing which through its capacity to cleave the internal linkage
between the glucose-substituted mannose and the remainder of the
polymannose carbohydrate unit can provide an alternate pathway for
achieving deglucosylation and thereby make possible the continued formation
of complex oligosaccharides during a glucosidase blockade. In view of the
important role which has been attributed to glucose on nascent
glycoproteins as a regulator of a number of biological events, we chose to
further define the in vivo action of endomannosidase by focusing on the
well characterized VSV envelope glycoprotein (G protein) which can be
formed by the large array of cell lines susceptible to infection by this
pathogen. Through an assessment of the extent to which the G protein was
converted to an endo-beta-N- acetylglucosaminidase (endo H)-resistant form
during a castanospermine imposed glucosidase blockade, we found that
utilization of the endomannosidase-mediated deglucosylation route was
clearly host cell specific, ranging from greater than 90% in HepG2 and PtK1
cells to complete absence in CHO, MDCK, and MDBK cells, with intermediate
values in BHK, BW5147.3, LLC-PK1, BRL, and NRK cell lines. In some of the
latter group the electrophoretic pattern after endo H treatment suggested
that only one of the two N-linked oligosaccharides of the G protein was
processed by endomannosidase. In the presence of the specific
endomannosidase inhibitor, Glcalpha1-->3(1- deoxy)mannojirimycin, the
conversion of the G protein into an endo H- resistant form was completely
arrested. While the lack of G protein processing by CHO cells was
consistent with the absence of in vitro measured endomannosidase activity
in this cell line, the failure of MDBK and MDCK cells to convert the G
protein into an endo H-resistant form was surprising since these cell lines
have substantial levels of the enzyme. Similarly, we observed that
influenza virus hemagglutinin was not processed in castanospermine-treated
MDCK cells. Our findings suggest that studies which rely on glucosidase
inhibition to explore the function of glucose in controlling such critical
biological phenomena as intracellular movement or quality control should be
carried out in cell lines in which the glycoprotein under study is not a
substrate for endomannosidase action.
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