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61.
Khanh Dang Vu S. Yan R.D. Tyagi J.R. Valéro R.Y. Surampalli 《Bioresource technology》2009,100(21):5260-5269
Induced production of chitinase during bioconversion of starch industry wastewater (SIW) to Bacillus thuringiensis var. kurstaki HD-1 (Btk) based biopesticides was studied in shake flask as well as in computer-controlled fermentors. SIW was fortified with different concentrations (0%; 0.05%; 0.1%; 0.2%; 0.3% w/v) of colloidal chitin and its consequences were ascertained in terms of Btk growth (total cell count and viable spore count), chitinase, protease and amylase activities and entomotoxicity. At optimum concentration of 0.2% w/v colloidal chitin, the entomotoxicity of fermented broth and suspended pellet was enhanced from 12.4 × 109 (without chitin) to 14.4 × 109 SBU/L and from 18.2 × 109 (without chitin) to 25.1 × 109 SBU/L, respectively. Further, experiments were conducted for Btk growth in a computer-controlled 15 L bioreactor using SIW as a raw material with (0.2% w/v chitin, to induce chitinase) and without fortification of colloidal chitin. It was found that the total cell count, spore count, delta-endotoxin concentration (alkaline solubilised insecticidal crystal proteins), amylase and protease activities were reduced whereas the entomotoxicity and chitinase activity was increased with chitin fortification. The chitinase activity attained a maximum value at 24 h (15 mU/ml) and entomotoxicity of suspended pellet reached highest (26.7 × 109 SBU/L) at 36 h of fermentation with chitin supplementation of SIW. In control (without chitin), the highest value of entomotoxicity of suspended pellet (20.5 × 109 SBU/L) reached at 48 h of fermentation. A quantitative synergistic action of delta-endotoxin concentration, spore concentration and chitinase activity on the entomotoxicity against spruce budworm larvae was observed. 相似文献
62.
We have studied the morphology and vein branching of rosette leaves in Arabidopsis thaliana mutants as and sa, which proved to be alleles of the A.thaliana AS1 and AS2 genes, respectively. We have also analyzed the localization of bioactive auxin, as measured by the expression of the DR5::GUS transgene, as well as the expression patterns of BP, as measured by the expression of the BP::GUS transgene in leaves of the mutants. In mature leaves of the mutants, BP was expressed ectopically. Furthermore, the mutants showed some defects in the localization and concentration of free auxin compared to the wild type. Our results of studying new alleles of AS1 and AS2 support their role in control of class I KNOX genes and auxin transport. 相似文献
63.
Zhen-Yong Keck Sven G. Enterlein Katie A. Howell Hong Vu Sergey Shulenin Kelly L. Warfield Jeffrey W. Froude Nazli Araghi Robin Douglas Julia Biggins Calli M. Lear-Rooney Ariel S. Wirchnianski Patrick Lau Yong Wang Andrew S. Herbert John M. Dye Pamela J. Glass Frederick W. Holtsberg Steven K. H. Foung M. Javad Aman 《Journal of virology》2016,90(1):279-291
64.
Christopher S. Bland Eric T. Wang Anthony Vu Marjorie P. David John C. Castle Jason M. Johnson Christopher B. Burge Thomas A. Cooper 《Nucleic acids research》2010,38(21):7651-7664
Recent genome-wide analyses have elucidated the extent of alternative splicing (AS) in mammals, often focusing on comparisons of splice isoforms between differentiated tissues. However, regulated splicing changes are likely to be important in biological transitions such as cellular differentiation, or response to environmental stimuli. To assess the extent and significance of AS in myogenesis, we used splicing-sensitive microarray analysis of differentiating C2C12 myoblasts. We identified 95 AS events that undergo robust splicing transitions during C2C12 differentiation. More than half of the splicing transitions are conserved during differentiation of avian myoblasts, suggesting the products and timing of transitions are functionally significant. The majority of splicing transitions during C2C12 differentiation fall into four temporal patterns and were dependent on the myogenic program, suggesting that they are integral components of myogenic differentiation. Computational analyses revealed enrichment of many sequence motifs within the upstream and downstream intronic regions near the alternatively spliced regions corresponding to binding sites of splicing regulators. Western analyses demonstrated that several splicing regulators undergo dynamic changes in nuclear abundance during differentiation. These findings show that within a developmental context, AS is a highly regulated and conserved process, suggesting a major role for AS regulation in myogenic differentiation. 相似文献
65.
Y Suzuki W Wang T H Vu T A Raffin 《Biochemical and biophysical research communications》1992,184(3):1339-1343
Neutrophil adherence to endothelium is partially mediated by the expression of endothelial leukocyte adhesion molecule-1 (ELAM-1) on endothelial cells activated by agents such as lipopolysaccharide (LPS) and phorbol myristate acetate (PMA). To elucidate molecular mechanisms involved in the induction of ELAM-1 on endothelial cells, we investigated the effect of the NADPH oxidase inhibitor, apocynin (4-hydroxy-3-methoxyacetophenone), on ELAM-1 mRNA expression in human umbilical vein endothelial cells (HUVEC) by Northern blot analysis. Apocynin downregulated both LPS- and PMA-induced ELAM-1 mRNA expression in a dose-dependent manner. Our results suggest NADPH oxidase might play a key role in ELAM-1 mRNA expression in HUVEC. 相似文献
66.
Allen R. Rhoads Rabin Parui Ngoc-Diep Vu Robert Cadogan Paul D. Wagner 《Journal of neurochemistry》1993,61(5):1657-1666
Abstract— Secretion of catecholamines by rat PC12 cells is strongly stimulated by extracellular ATP via a P2 -type pur-inergic receptor. ATP-induced norepinephrine release was inhibited 80% when extracellular Ca2+ was absent. Only four nucleotides, ATP, ATPγS, benzoylbenzoyl ATP (BzATP), and 2-methylthio-ATP, gave substantial stimulation of norepinephrine release from PC12 cells. ATP-induced secretion was inhibited by Mg2+ , and this inhibition was overcome by the addition of excess ATP suggesting that ATP4- was the active ligand. ATP-induced secretion of catecholamine release was enhanced by treatment of cells with pertussis toxin or 12- O -tetradecanoylphorbol 13-acetate. The stimulatory effects of 12- O -tetradecanoyl-phorbol 13-acetate and pertussis toxin on norepinephrine release were additive. After brief exposure of intact cells to the photoaffinity analog, [α-32 P]BzATP, two major proteins of 44 and 50 kDa and a minor protein of 97 kDa were labeled. An excess of ATP-γS and BzATP but not GTP blocked labeling of the proteins by [32 P]BzATP. Labeling of the 50-kDa protein was more sensitive to competition by 2-methylthio-ATP than the other labeled proteins, suggesting that the 50-kDa protein represents the P2 receptor responsible for ATP-stimulated secretion in these cells. 相似文献
67.
Vu H Ianosi-Irimie M Danchuk S Rabon E Nogawa T Kamano Y Pettit GR Wiese T Puschett JB 《Experimental biology and medicine (Maywood, N.J.)》2006,231(2):215-220
The study of the pathogenesis of preeclampsia has been hampered by a relative dearth of animal models. We developed a rat model of preeclampsia in which the excretion of a circulating inhibitor of Na/K ATPase, marinobufagenin (MBG), is elevated. These animals develop hypertension, proteinuria, and intrauterine growth restriction. The administration of a congener of MBG, resibufogenin (RBG), reduces blood pressure to normal in these animals, as is the case when given to pregnant animals rendered hypertensive by the administration of MBG. Studies of Na/K ATPase inhibition by MBG and RBG reveal that these agents are equally effective as inhibitors of the enzyme. 相似文献
68.
Heiman F. L. Wertheim Huyen Nguyen Nguyen Walter Taylor Trinh Thi Minh Lien Hoa Thi Ngo Thai Quoc Nguyen Bich Ngoc Thi Nguyen Ha Hong Nguyen Ha Minh Nguyen Cap Trung Nguyen Trinh Tuyet Dao Trung Vu Nguyen Annette Fox Jeremy Farrar Constance Schultsz Hien Duc Nguyen Kinh Van Nguyen Peter Horby 《PloS one》2009,4(6)
Background
Streptococcus suis can cause severe systemic infection in adults exposed to infected pigs or after consumption of undercooked pig products. S. suis is often misdiagnosed, due to lack of awareness and improper testing. Here we report the first fifty cases diagnosed with S. suis infection in northern Viet Nam.Methodology/Principal Findings
In 2007, diagnostics for S. suis were set up at a national hospital in Hanoi. That year there were 43 S. suis positive cerebrospinal fluid samples, of which S. suis could be cultured in 32 cases and 11 cases were only positive by PCR. Seven patients were blood culture positive for S. suis but CSF culture and PCR negative; making a total of 50 patients with laboratory confirmed S. suis infection in 2007. The number of S. suis cases peaked during the warmer months.Conclusions/Significance
S. suis was commonly diagnosed as a cause of bacterial meningitis in adults in northern Viet Nam. In countries where there is intense and widespread exposure of humans to pigs, S. suis can be an important human pathogen. 相似文献69.
Tran Vu Thien Hoang Ngoc Anh Nguyen Thi Thuy Trang Phung Van Trung Nguyen Cuu Khoa A. V. Osipov P. V. Dubovskii I. A. Ivanov A. S. Arseniev V. I. Tsetlin Yu. N. Utkin 《Doklady. Biochemistry and biophysics》2017,476(1):316-319
Low-molecular-weight compounds with anticoagulant activity were isolated from the scorpion Heterometrus laoticus venom. The determination of the structure of the isolated compounds by nuclear magnetic resonance and mass spectrometry showed that one of the isolated compounds is adenosine, and the other two are dipeptides leucyl-tryptophan and isoleucyl-tryptophan. The anticoagulant properties of adenosine, which is an inhibitor of platelet aggregation, is well known, but its presence in scorpion venom is shown for the first time. The ability of leucyl-tryptophan and isoleucyl-tryptophan to slow down blood clotting and their presence in scorpion venom are also established for the first time. 相似文献
70.
Different pH control agents (NaOH/H2SO4—SodSulp, NaOH/CH3COOH—SodAcet, NH4OH/CH3COOH—AmmoAcet and NH4OH/H2SO4—AmmoSulp) were used to investigate their effects on growth, enzyme production (alkaline protease and amylase), and entomotoxicity
of Bacillus thuringiensis var. kurstaki HD-1 (Btk) against eastern spruce budworm larvae (Choristoneura fumiferana) using starch industry wastewater (SIW) as a raw material in a 15-l fermentor. AmmoSulp and SodSulp were found to be the
best pH control agents for alkaline protease and amylase production, respectively; whereas, the fermented broth obtained by
using SodAcet as pH control agents recorded the highest delta-endotoxin production of 1043.0 mg/l and entomotoxicity value
18.4 × 109 SBU/l. Entomotoxicity of re-suspended centrifuged pellet in one-tenth of original volume in case of SodAcet as pH control
agents was 26.7 × 109 SBU/l and was the highest value compared to three other pH control agents. 相似文献