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101.
Nirogi RV Deshpande AD Kambhampati R Badange RK Kota L Daulatabad AV Shinde AK Ahmad I Kandikere V Jayarajan P Dubey PK 《Bioorganic & medicinal chemistry letters》2011,21(1):346-349
N1-Arylsulfonyl-3-piperazinyl indole derivatives were designed and identified as a novel class of 5-HT6 receptors ligands. All the compounds have high affinity and antagonist activity towards 5-HT6 receptor. The compound 7a (Ki = 3.4 nM, functional assay IC50 = 310 nM) shows enhanced cognitive effect when tested in NORT and Morris water maze models. Synthesis, SAR and PK profile of these novel compounds constitute the subject matter of this Letter. 相似文献
102.
The abundance and inherent potential for variations in simple sequence repeats (SSRs) or microsatellites resulted in valuable source for genetic markers in
eukaryotes. We describe the organization and abundance of SSRs in fungus Fusarium graminearum (causative agent for Fusarium head blight or head
scab of wheat). We identified 1705 SSRs of various nucleotide repeat motifs in the sequence database of F. graminearum. It is observed that
mononucleotide repeats (62%) were most abundant followed by di- (20%) and trinucleotide repeats (14%). It is noted that tetra-, penta- and
hexanucleotide repeats accounted for only 4% of SSRs. The estimated frequency of Class I SSRs (perfect repeats ≥20 nucleotides) was one SSR per 124.5
kb, whereas the frequency of Class II (perfect repeats >10 nucleotides and ≫20 nucleotides) was one SSR per 25.6 kb. The dynamics of SSRs will be a
powerful tool for taxonomic, phylogenetic, genome mapping and population genetic studies as SSR based markers show high levels of allelic variation,
codominant inheritance and ease of analysis. 相似文献
103.
Olszewski WL Jain P Ambujam G Zaleska M Cakala M Gradalski T 《Lymphatic research and biology》2011,9(2):77-83
Background: Physiotherapy of edema in cases with obstructed main lymphatics of lower limbs requires knowledge of how high external pressures should be applied manually or set in compression devices in order to generate tissue pressures high enough to move tissue fluid to nonswollen regions and to measure its flow rate. Methods: We measured tissue fluid pressure and flow in subcutaneous tissue of lymphedematous limbs stages II to IV at rest and during pneumatic compression under various pressures and inflation timing. An 8-chamber sequential compression device inflated to pressures 50-120?mmHg, for 50 sec each chamber, with no distal deflation, was used. Pressures were measured using a wick-in-needle and electronic manometer. Fluid flow was calculated from continuously recorded changes in limb circumference using strain gauge plethysmography. Results: Before massage, in all stages of lymphedema, stagnant tissue fluid pressures in subcutaneous tissue ranged between -1 and +10 mmHg and did not differ from those measured in normal subjects. Pressures generated in tissue fluid by pneumatic compression reached 40-100 mmHg and were lower than those in inflated chambers. High pressure gradient through the skin was caused by its rigidity (fibrosis) and dissipation of applied compression force to proximal noncompressed limb regions. The calculated volumes of displaced tissue fluid ranged from 10 to 30 ml per compression cycle, to reach in some cases 100 ml in the groin region. Conclusions: Tissue fluid pressures generated by a pneumatic device were found lower than in the compression chambers. The obtained results point to the necessity of applying high pressures and longer compression times to generate effective tissue fluid pressures and to provide enough time for moving the stagnant fluid. 相似文献
104.
SAG101 forms a ternary complex with EDS1 and PAD4 and is required for resistance signaling against turnip crinkle virus 总被引:1,自引:0,他引:1
Zhu S Jeong RD Venugopal SC Lapchyk L Navarre D Kachroo A Kachroo P 《PLoS pathogens》2011,7(11):e1002318
EDS1, PAD4, and SAG101 are common regulators of plant immunity against many pathogens. EDS1 interacts with both PAD4 and SAG101 but direct interaction between PAD4 and SAG101 has not been detected, leading to the suggestion that the EDS1-PAD4 and EDS1-SAG101 complexes are distinct. We show that EDS1, PAD4, and SAG101 are present in a single complex in planta. While this complex is preferentially nuclear localized, it can be redirected to the cytoplasm in the presence of an extranuclear form of EDS1. PAD4 and SAG101 can in turn, regulate the subcellular localization of EDS1. We also show that the Arabidopsis genome encodes two functionally redundant isoforms of EDS1, either of which can form ternary complexes with PAD4 and SAG101. Simultaneous mutations in both EDS1 isoforms are essential to abrogate resistance (R) protein-mediated defense against turnip crinkle virus (TCV) as well as avrRps4 expressing Pseudomonas syringae. Interestingly, unlike its function as a PAD4 substitute in bacterial resistance, SAG101 is required for R-mediated resistance to TCV, thus implicating a role for the ternary complex in this defense response. However, only EDS1 is required for HRT-mediated HR to TCV, while only PAD4 is required for SA-dependent induction of HRT. Together, these results suggest that EDS1, PAD4 and SAG101 also perform independent functions in HRT-mediated resistance. 相似文献
105.
106.
Puligundla P Smogrovicova D Obulam VS Ko S 《Journal of industrial microbiology & biotechnology》2011,38(9):1133-1144
There have been numerous developments in ethanol fermentation technology since the beginning of the new millennium as ethanol
has become an immediate viable alternative to fast-depleting crude reserves as well as increasing concerns over environmental
pollution. Nowadays, although most research efforts are focused on the conversion of cheap cellulosic substrates to ethanol,
methods that are cost-competitive with gasoline production are still lacking. At the same time, the ethanol industry has engaged
in implementing potential energy-saving, productivity and efficiency-maximizing technologies in existing production methods
to become more viable. Very high gravity (VHG) fermentation is an emerging, versatile one among such technologies offering
great savings in process water and energy requirements through fermentation of higher concentrations of sugar substrate and,
therefore, increased final ethanol concentration in the medium. The technology also allows increased fermentation efficiency,
without major alterations to existing facilities, by efficient utilization of fermentor space and elimination of known losses.
This comprehensive research update on VHG technology is presented in two main sections, namely VHG brewing, wherein the effects
of nutrients supplementation, yeast pitching rate, flavour compound synthesis and foam stability under increased wort gravities
are discussed; and VHG bioethanol fermentation studies. In the latter section, aspects related to the role of osmoprotectants
and nutrients in yeast stress reduction, substrates utilized/tested so far, including saccharide (glucose, sucrose, molasses,
etc.) and starchy materials (wheat, corn, barley, oats, etc.), and mash viscosity issues in VHG bioethanol production are
detailed. Thereafter, topics common to both areas such as process optimization studies, mutants and gene level studies, immobilized
yeast applications, temperature effect, reserve carbohydrates profile in yeast, and economic aspects are discussed and future
prospects are summarized. 相似文献
107.
Ihsan R Chauhan PS Mishra AK Yadav DS Kaushal M Sharma JD Zomawia E Verma Y Kapur S Saxena S 《PloS one》2011,6(12):e29431
Complex disease such as cancer results from interactions of multiple genetic and environmental factors. Studying these factors singularly cannot explain the underlying pathogenetic mechanism of the disease. Multi-analytical approach, including logistic regression (LR), classification and regression tree (CART) and multifactor dimensionality reduction (MDR), was applied in 188 lung cancer cases and 290 controls to explore high order interactions among xenobiotic metabolizing genes and environmental risk factors. Smoking was identified as the predominant risk factor by all three analytical approaches. Individually, CYP1A1*2A polymorphism was significantly associated with increased lung cancer risk (OR = 1.69;95%CI = 1.11–2.59,p = 0.01), whereas EPHX1 Tyr113His and SULT1A1 Arg213His conferred reduced risk (OR = 0.40;95%CI = 0.25–0.65,p<0.001 and OR = 0.51;95%CI = 0.33–0.78,p = 0.002 respectively). In smokers, EPHX1 Tyr113His and SULT1A1 Arg213His polymorphisms reduced the risk of lung cancer, whereas CYP1A1*2A, CYP1A1*2C and GSTP1 Ile105Val imparted increased risk in non-smokers only. While exploring non-linear interactions through CART analysis, smokers carrying the combination of EPHX1 113TC (Tyr/His), SULT1A1 213GG (Arg/Arg) or AA (His/His) and GSTM1 null genotypes showed the highest risk for lung cancer (OR = 3.73;95%CI = 1.33–10.55,p = 0.006), whereas combined effect of CYP1A1*2A 6235CC or TC, SULT1A1 213GG (Arg/Arg) and betel quid chewing showed maximum risk in non-smokers (OR = 2.93;95%CI = 1.15–7.51,p = 0.01). MDR analysis identified two distinct predictor models for the risk of lung cancer in smokers (tobacco chewing, EPHX1 Tyr113His, and SULT1A1 Arg213His) and non-smokers (CYP1A1*2A, GSTP1 Ile105Val and SULT1A1 Arg213His) with testing balance accuracy (TBA) of 0.6436 and 0.6677 respectively. Interaction entropy interpretations of MDR results showed non-additive interactions of tobacco chewing with SULT1A1 Arg213His and EPHX1 Tyr113His in smokers and SULT1A1 Arg213His with GSTP1 Ile105Val and CYP1A1*2C in nonsmokers. These results identified distinct gene-gene and gene environment interactions in smokers and non-smokers, which confirms the importance of multifactorial interaction in risk assessment of lung cancer. 相似文献
108.
109.
Minimal cross-recombination between wild-type and loxP511 sites in vivo facilitates truncating both ends of large DNA inserts in pBACe3.6 and related vectors 下载免费PDF全文
Shakes LA Garland DM Srivastava DK Harewood KR Chatterjee PK 《Nucleic acids research》2005,33(13):e118
Contrary to several earlier reports, we find that cross-recombination between wild-type and the mutant loxP511 sites is <0.5% of that between two wild-type sites if Cre protein is expressed by phage P1 during an infection. The finding enabled us to develop a procedure to truncate DNA progressively from both ends of large genomic inserts flanked by these two loxP sites in pBACe3.6 and related vectors with transposons carrying either a wild-type or a loxP511 sequence. Newly constructed loxP511 transposons contained either a kanamycin resistance gene or no marker. Insert DNA ends in deletions were sequenced with primers unique to each transposon-end remaining after the respective recombination. End-sequencing 223 deletions confirmed that the low level of cross-recombination, observed between those sites during the P1 transductions, does not complicate the procedure: truncations from the unintended end of genomic inserts did not occur. Multiple BACs pooled together could also be processed in a single tube to make end-deletions. This deletion technology, utilizing the very minimal cross-recombination between the mutant and wild-type loxP sites of most BAC clones in the public domain and a heterologous one inserted as a transposon, should facilitate functionally mapping long-range gene regulatory sequences and help to isolate genes with defined functional boundaries in numerous projects including those of therapeutic interest. 相似文献
110.
Phage Bacteriolysis, Protistan Bacterivory Potential, and Bacterial Production in a Freshwater Reservoir: Coupling with Temperature 总被引:1,自引:0,他引:1
Phage abundance and infection of bacterioplankton were studied from March to November 2003 in the Sep Reservoir (Massif Central,
France), together with temperature, chlorophyll, bacteria (abundance and production), and heterotrophic nanoflagellates (abundance
and potential bacterivory). Virus abundance (VA) ranged from 0.6 to 13 × 1010 viruses l−1, exceeding bacterial abundance (BA) approximately sixfold on average. In terms of carbon, viruses corresponded to up to 25%
of bacterial biomass. A multiple regression model indicated that BA was the best predictor for VA (R2 = 0.75). The frequency of infected bacteria (estimated from the percentage of visibly infected cells) varied from 1% to 32%
and was best explained by a combination of temperature (R2 = 0.20) and bacterial production (R2 = 0.25). Viruses and flagellates contributed about equally to bacterial mortality. Both factors destroyed 55% of bacterial
production, with a shift from phage bacteriolysis in early spring to protistan bacterivory in late summer. The vertical differences
in most of the biological variables were not significant, contrasting with the seasonal differences (i.e., spring vs. summer-autumn).
All biological variables under study were indeed significantly coupled to temperature. We regarded this to be the consequence
of the enhanced discharge of the reservoir in 2003 (compared to previous years). This substantially weakened the stability
and the thermal inertia of the water column, thereby establishing temperature as a stronger forcing factor in setting the
conditions for optimal metabolic activity of microbial communities. 相似文献