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61.
Nakahara H Nishimura S Inoue M Hori G Amari S 《Bioinformatics (Oxford, England)》2003,19(9):1124-1131
MOTIVATION: Given the vast amount of gene expression data, it is essential to develop a simple and reliable method of investigating the fine structure of gene interaction. We show how an information geometric measure achieves this. RESULTS: We introduce an information geometric measure of binary random vectors and show how this measure reveals the fine structure of gene interaction. In particular, we propose an iterative procedure by using this measure (called IPIG). The procedure finds higher-order dependencies which may underlie the interaction between two genes of interest. To demonstrate the method, we investigate the interaction between the two genes of interest in the data from human acute lymphoblastic leukemia cells. The method successfully discovered biologically known findings and also selected other genes as hidden causes that constitute the interaction. AVAILABILITY: Softwares are currently not available but are possibly made available in future at http://www.mns.brain.riken.go.jp/~nakahara/DNA_pub.html where all the related information is also linked. 相似文献
62.
Feugang JM Van Langendonckt A Sayoud H Rees JF Pampfer S Moens A Dessy F Donnay I 《Zygote (Cambridge, England)》2003,11(2):107-118
Two prooxidant agents, 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH), a generator of free radicals in the culture medium, and buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis, were used to reinforce from the morula stage (day 5 post-insemination, p.i.) the oxidative stress encountered by bovine embryos in culture. Exposure to increasing concentrations of both prooxidants from the morula stage did not affect blastocyst formation but some blastocysts were found degenerated on day 8 in a dose-dependent manner (0, 0.001, 0.01, 0.1 mM AAPH gave respectively 0, 10%, 32%, 48% degeneration, while 0, 0.1, 0.2, 0.4 mM BSO led respectively to 0, 14%, 30%, 41% degeneration). Hatching rates and cell numbers of surviving blastocysts were not affected. Morulae and early blastocysts exposed from day 5 to day 6 p.i. appeared more resistant than expanded blastocysts (75-80% survival vs 20-65%; p < 0.05). Treatment with BSO significantly decreased the level of reduced glutathione in day 7 blastocysts (0.02 vs 0.42 pmol per embryo in the control) while AAPH had no effect (0.38 pmol per embryo). The proportion ofcells showing membrane lesions was increased in degenerated blastocysts from day 7.5 p.i. In AAPH-treated, but not in BSO-treated embryos, cell membrane permeabilisation seems to occur before blastocyst degeneration. DNA fragmentation evaluated by the TUNEL technique was increased in day 7 blastocysts by both prooxidants (2.8 +/- 0.4 in the control group vs 4.5 +/- 0.4 and 6.0 +/- 0.4 respectively in the AAPH- and BSO-treated groups). Addition of an inhibitor of caspase-3, DEVD-CHO, partially prevented DNA fragmentation, indicating that prooxidant treatment induced a caspase-dependent pathway of apoptosis. 相似文献
63.
Mayssa Ben Mustapha Faisal K. Algethami Mohamed R. Elamin Babiker Y. Abdulkhair Ikbal Chaieb Hichem Ben Jannet 《化学与生物多样性》2023,20(3):e202200978
In this work, essential oils extracted from roots and aerial parts of Inula graveolens by hydrodistillation and their fractions obtained by chromatographic simplification were first investigated for their chemical composition by GC/MS and then evaluated for the first time for their repellency and contact toxicity properties against Tribolium castaneumadults. Twenty-eight compounds were identified in roots essential oil (REO), which accounted for 97.9 % of the total oil composition, with modhephen-8-β-ol (24.7 %), cis-arteannuic alcohol (14.8 %), neryl isovalerate (10.6 %) and thymol isobutyrate (8.5 %) as major constituents. Twenty-two compounds were found in the essential oil from aerial parts (APEO), which accounted for 93.9 % of the total oil, with borneol (28.8 %), caryophylla-4(14),8(15)-dien-6-ol (11.5 %), caryophyllene oxide (10.9 %), τ-cadinol (10.5 %) and bornyl acetate (9.4 %) as main compounds.REO and APEO displayed stronger repellency after 2 h of exposure (80.0 and 90.0 %, respectively) against T. castaneum at the concentration of 0.12 μL/cm2. After fractionation, fractions R4 and R5 exhibited greater effects (83.3 % and 93.3 %, respectively) than the roots essential oil. Furthermore, the fractions AP2 and AP3 showed higher repellency (93.3 and 96.6 %, respectively) than the aerial parts oil. The LD50 values of oils from roots and aerial parts topically applied were 7.44 % and 4.88 %, respectively. Results from contact toxicity assay showed that fraction R4 was more effective than the roots oil with LD50 value of 6.65 %. These results suggests that essential oils of roots and aerial parts from I. graveolens may be explored as potential natural repellent and contact insecticides against T. castaneum in stored products. 相似文献
64.
PCR detection of DNAs of animal origin in feed by primers based on sequences of short and long interspersed repetitive elements 总被引:5,自引:0,他引:5
Tajima K Enishi O Amari M Mitsumori M Kajikawa H Kurihara M Yanai S Matsui H Yasue H Mitsuhashi T Kawashima T Matsumoto M 《Bioscience, biotechnology, and biochemistry》2002,66(10):2247-2250
PCR primers for the detection of materials derived from ruminants, pigs, and chickens were newly designed on the basis of sequences of the Art2 short interspersed repetitive element (SINE), PRE-1 SINE, and CR1 long interspersed repetitive element (LINE), respectively. These primers amplified the SINE or LINE from total DNA extracted from the target animals and from test feed containing commercial meat and bone meal (MBM). With the primers, detection of Art2, PRE-1, or CR1 in test feed at concentrations of 0.01% MBM or less was possible. This method was suitable for the detection of microcontamination of feed by animal materials. 相似文献
65.
Minadeo N Layden B Amari LV Thomas V Radloff K Srinivasan C Hamm HE de Freitas DM 《Archives of biochemistry and biophysics》2001,388(1):7-12
Although lithium salts have been used in the treatment and prophylaxis of manic-depressive or bipolar patients for 50 years, the mechanism of the pharmacologic action of Li+ is unknown. Based on activity studies of inhibitory and stimulatory guanine-binding (G) proteins in rat cortical membranes, it was proposed that Li+ inhibition of G-proteins may account for its pharmacologic action. We used the purified alpha subunit of the recombinant inhibitory G-protein, rGialpha1, and found that Li+ at therapeutic levels significantly inhibited the formation of the GDP.AlF4-.rGialpha1 complex. Because our studies were conducted with a purified, metal-reconstituted G-protein rather than with cell membrane suspensions, our Li+ inhibition results lend additional support to the G-protein hypothesis for Li+ action. 相似文献
66.
Nejla Soudani Moez Rafrafi Ibtissem Ben Amara Ahmed Hakim Afef Troudi Khaled Mounir Zeghal Hichem Ben Salah Tahia Boudawara Najiba Zeghal 《Journal of physiology and biochemistry》2013,69(2):239-253
Chromium(VI), a very strong oxidant, causes high cytotoxicity through oxidative stress in tissue systems. Our study investigated the potential ability of ethanolic Citrus aurantium L., family Rutaceae extract, used as a nutritional supplement, to alleviate lung oxidative damage induced by Cr(VI). A high-performance liquid chromatography coupled with a mass spectrometer method was developed to separate and identify flavonoids in C. aurantium L. Six flavonoids were identified, as (1) poncirin, (2) naringin, (3) naringenin, (4) quercetin, (5) isosinensetin, and (6) tetramethyl-o-isoscutellarein. Adult Wistar rats, used in this study, were divided into six groups of six animals each: group I served as controls which received standard diet, group II received via drinking water K2Cr2O7 alone (700 ppm), groups III and IV were pretreated for 10 days with ethanol extract of C. aurantium L. at doses of 100 and 300 mg/kg body weight/day, respectively, and then K2Cr2O7 was administrated during 3 weeks, and groups V and VI received during 10 days only C. aurantium L. ethanol extract at doses of 100 and 300 mg/kg/day, respectively. Ethanol extract of C. aurantium L. was administered orally. Rats exposed to Cr(VI) showed in lung an increase in malondialdehyde and protein carbonyl levels and a decrease in sulflydryl content, glutathione, nonprotein thiol, and vitamins C and E levels. Decreases in enzyme activities such as in Na+K+ ATPase, catalase, glutathione peroxidase, and superoxide dismutase were noted. Pretreatment with C. aurantium L. of chromium-treated rats ameliorated all biochemical parameters. Lung histological studies confirmed the biochemical parameters and the beneficial role of C. aurantium L. 相似文献
67.
Lamia Lahouar Fatma Ghrairi Mouldi El Felah Hichem Ben Salem Abdel Hedi Miled Mohamed Hammami Lotfi Achour 《Journal of physiology and biochemistry》2011,67(1):27-34
The aim of the present study is to evaluate the effects of diet enriched with dietary fiber of barley variety “Rihane” and
azoxymethane on serum and liver lipid variables in male rats. Forty male rats were divided into four groups and fed on control
diet or experimental diet that contained control enriched with dietary fiber of barley variety “Rihane”. Animals were injected
with saline (controls) or azoxymethane (20 mg/kg body weight s.c.) at 7 and 8 weeks of age. The experimental diet significantly
decreased cholesterol level compared with the control diet. Rats fed with BR diet significantly increased the serum high-density
lipoprotein (HDL) cholesterol and significantly decreased low-density lipoprotein (LDL) cholesterol concentrations. The experimental
diet decreased the atherogenic index (p < 0.05) compared with the control diet. Whereas the azoxymethane induced a significant increase of liver lipid, serum LDL
and triglyceride concentrations, but it caused a significant reduction of HDL. Consequently, the ratio of HDL/TC decreased
significantly compared with the control (p < 0.05). Accordingly, these results indicated that the diet enriched with dietary fiber of barley variety “Rihane” could
be effective in decreasing the atherogenic risk factors in rats whereas the use of the azoxymethane as colon-specific carcinogen
substance altered the lipid metabolism. 相似文献
68.
Luna-Acosta A Thomas-Guyon H Amari M Rosenfeld E Bustamante P Fruitier-Arnaudin I 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2011,159(4):220-226
Phenoloxidases (POs) play a key role in melanin production, are involved in invertebrate immune mechanisms, and have been detected in different bivalves. Recently, we identified catecholase- and laccase-like PO activities in plasma and haemocyte lysate supernatant (HLS) of the Pacific oyster Crassostrea gigas. To go further in our investigations, the aims of this study were (i) to determine the tissue distribution of PO activities in C. gigas, and (ii) to identify and characterise the different sub-classes of POs (i.e. tyrosinase, catecholase and/or laccase) involved in these oxido-reductase activities. With dopamine and p-phenylenediamine (PPD) but not with l-tyrosine used as substrates, PO-activities were detected by spectrophotometry in the gills, digestive gland, mantle, and muscle. These results suggest the presence of catecholase and laccase but not of tyrosinase activities in oyster tissues. The highest activity was recovered in the digestive gland. PO-like activities were all inhibited by 1-phenyl-2-thiourea (PTU) and by the specific laccase inhibitor, cethyltrimethylammonium bromide (CTAB). With dopamine as substrate, the catecholase inhibitor 4-hexylresorcinol (4-HR) only inhibited PO in the muscle. SDS-PAGE zymographic assays with dopamine and PPD elicited a unique ~40kDa protein band in the muscle. In the other tissues, laccase-like activities could be related to ~10kDa and/or ~200kDa protein bands. The ~10kDa protein band was also detected in plasma and HLS, confirming the presence of a laccase in the later compartments, and probably in most of the tissues of C. gigas. This is the first time to our knowledge that a ~10kDa protein band is associated to a laccase-like activity in a mollusc species, contributing to the characterisation of phenoloxidase activities in marine bivalves. 相似文献
69.
Mayssa Ben Mustapha Afifa Zardi‐Bergaoui Ikbel Chaieb Guido Flamini Roberta Ascrizzi Hichem Ben Jannet 《化学与生物多样性》2020,17(3)
Several plant essential oils have been used against diverse insect pests since, unlike conventional pesticides, they pose almost no risk to humans and the environment. For this reason, the essential oil (EO) isolated from the fresh leaves of Crithmum maritimum L. and its fractions (F1–F5) obtained by chromatographic simplification were investigated for their chemical profile, as well as for their toxicity and repellency effects against Tribolium castaneum (Herbst ) adults. The analysis by GC/MS allowed the identification of 92.8–99.1 % of the compositions of the total oil (EO) and of its fractions (F1–F5). The EO and its fractions F3–F5 were characterized by the presence of a high amount of phenylpropanoids (94.4, 94.8, 93.6, and 88.7 %, respectively): in all the samples, dill apiole was the most abundant component (EO: 94.1 %, F3: 94.6 %, F4: 93.4 %, and F5: 83.3 %). In addition, the repellency assay results showed that the volatile fraction F5 and the complete EO exhibited a higher repellency towards T. castaneum (97 % and 93 %, respectively) after 2 h of exposure at the dose of 0.04 μL/cm2. The median lethal dose of the topical application of the EO was 9 %. Furthermore, the fraction F1 possessed interesting contact toxicity against T. castaneum (80 % of mortality) at the concentration of 10 %. These results suggested that the essential oil of C. maritimum leaves might be used as an alternative to synthetic insecticides in order to prevent insects from damaging the stored products. 相似文献
70.
Bis(monoacylglycero)phosphate (BMP) is one of the most intriguing classes of lipids discovered to date. Its biosynthetic pathway
is still not fully known, even though studies point to cardiolipin and PG as sources. BMP has an unusual stereoconfiguration
which is responsible for its slow catabolism. It is localized exclusively in the inner membranes of late endosomes, and mostly,
lysosomes. BMP is negatively charged at the acidic pH of lysosomes, and these charges are central to its role in the degradation
of lipids and membranes in the lysosome. In effect, these negative charges facilitate the adhesion of the soluble positively
charged hydrolases and activator proteins, thus allowing them to degrade the lipids at the interface of the inner membranes
of the lysosome. In this review, we will summarize the different properties of BMP and showcase its importance in the catabolism
of lipids and membranes in the lysosome. 相似文献