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991.
Song-sheng Shi Wei-zhong Yang Ye Chen Jian-ping Chen Xian-kun Tu 《Neurochemical research》2014,39(5):793-799
Our previous studies demonstrated that inflammatory reaction and neuronal apoptosis are the most important pathological mechanisms in ischemia-induced brain damage. Propofol has been shown to attenuate ischemic brain damage via inhibiting neuronal apoptosis. The present study was performed to evaluate the effect of propofol on brain damage and inflammatory reaction in rats of focal cerebral ischemia. Sprague–Dawley rats underwent permanent middle cerebral artery occlusion, then received treatment with propofol (10 or 50 mg/kg) or vehicle after 2 h of ischemia. Neurological deficit scores, cerebral infarct size and morphological characteristic were measured 24 h after cerebral ischemia. The enzymatic activity of myeloperoxidase (MPO) was assessed 24 h after cerebral ischemia. Nuclear factor-kappa B (NF-κB) p65 expression in ischemic rat brain was detected by western blot. Cyclooxygenase-2 (COX-2) expression in ischemic rat brain was determined by immunohistochemistry. ELISA was performed to detect the serum concentration of tumor necrosis factor-α (TNF-α). Neurological deficit scores, cerebral infarct size and MPO activity were significantly reduced by propofol administration. Furthermore, expression of NF-κB, COX-2 and TNF-α were attenuated by propofol administration. Our results demonstrated that propofol (10 and 50 mg/kg) reduces inflammatory reaction and brain damage in focal cerebral ischemia in rats. Propofol exerts neuroprotection against ischemic brain damage, which might be associated with the attenuation of inflammatory reaction and the inhibition of inflammatory genes. 相似文献
992.
Claudia Hoenemann Sandra Richardt Katja Krüger Andreas D Zimmer Annette Hohe Stefan A Rensing 《BMC plant biology》2010,10(1):77
Background
Clonal propagation is highly desired especially for valuable horticultural crops. The method with the potentially highest multiplication rate is regeneration via somatic embryogenesis. However, this mode of propagation is often hampered by the occurrence of developmental aberrations and non-embryogenic callus. Therefore, the developmental process of somatic embryogenesis was analysed in the ornamental crop Cyclamen persicum by expression profiling, comparing different developmental stages of embryogenic cell cultures, zygotic vs. somatic embryos and embryogenic vs. non-embryogenic cell cultures. 相似文献993.
Ana Flávia Azevedo Carvalho Maurício Boscolo Roberto da Silva Henrique Ferreira Eleni Gomes 《Journal of microbiology (Seoul, Korea)》2010,48(4):452-459
An α-glucosidase enzyme produced by the fungus Thermoascus aurantiacus CBMAI 756 was purified by ultra filtration, ammonium sulphate precipitation, and chromatography using Q Sepharose, Sephacryl
S-200, and Superose 12 columns. The apparent molecular mass of the enzyme was 83 kDa as determined in gel electrophoresis.
Maximum activity was observed at pH 4.5 at 70°C. Enzyme showed stability stable in the pH range of 3.0–9.0 and lost 40% of
its initial activity at the temperatures of 40, 50, and 60°C. In the presence of ions Na+, Ba2+, Co2+, Ni2+, Mg2+, Mn2+, Al3+, Zn2+, Ca2+ this enzyme maintained 90–105% of its maximum activity and was inhibited by Cr3+, Ag+, and Hg2+. The enzyme showed a transglycosylation property, by the release of oligosaccharides after 3 h of incubation with maltose,
and specificity for short maltooligosaccharides and α-PNPG. The Km measured for the α-glucosidase was 0.07 μM, with a Vmax of 318.0 μmol/min/mg. 相似文献
994.
Kristof De Prijck Nele De Smet Kris Honraet Steven Christiaen Tom Coenye Etienne Schacht Hans J. Nelis 《Mycopathologia》2010,169(3):167-174
Unlike various disinfectants, antifungals have not been commonly incorporated so far in medical devices, such as catheters
or prostheses, to prevent biofilm formation by Candida spp. In the present study, five antimycotics were added to polydimethyl siloxane (PDMS) disks via admixture (nystatin) or
impregnation (trimethylsilyl-nystatin (TMS-nystatin), miconazole, tea tree oil (TTO), zinc pyrithione). Nystatin-medicated
PDMS disks exhibited a concentration-dependent inhibitory effect on biofilm formation in a microtiter plate (MTP) but not
in a Modified Robbins Device (MRD). This observation, together with HPLC data and agar diffusion tests, indicates that a small
fraction of free nystatin is released, which kills Candida albicans cells in the limited volume of a MTP well. In contrast, biofilm inhibition amounted to more than one log unit in the MRD
on disks impregnated with miconazole, TTO, and zinc pyrithione. It is hypothesized that the reduction in biofilm formation
by these compounds in a flow system occurs through a contact-dependent effect. 相似文献
995.
Paul J. Buzzard 《Primates; journal of primatology》2010,51(4):307-314
Polyspecific associations (PSA) are common in many African primate communities, including the diurnal primates at Taï Forest, Côte d’Ivoire. In this paper I use data on the PSA of two forest guenons, Campbell’s (Cercopithecus campbelli) and lesser spot-nosed monkeys (C. petaurista), with Diana monkeys (C. diana) and other primates to clarify interspecific relationships during 17 months including a 3-month low-fruit period. I analyzed association in relation to fruit availability and measured forest strata use for C. campbelli and C. petaurista when alone and in associations with and without C. diana. I also measured predator risk and reactions to potential predators. C. campbelli and C. petaurista had high association rates with C. diana monkeys, and fruit availability did not influence association rates. C. campbelli and C. petaurista used higher strata when in association with C. diana than when alone, but they used even higher strata when associated with other primates without C. diana. This suggested that C. diana competitively exclude C. campbelli and C. petaurista from higher strata. There were relatively large numbers of potential predators, and C. diana were usually the first callers to threatening stimuli, suggesting that antipredator benefits of association with C. diana outweighed the competitive costs. C. campbelli spent more time in association with C. diana than C. petaurista did and appeared to be more reliant on C. diana for antipredator benefits. C. petaurista were less reliant on C. diana because of a cryptic strategy and may have associated less in some months because of high chimpanzee (Pan troglodytes) presence. 相似文献
996.
Saijai Panwichian Duangporn Kantachote Banjong Wittayaweerasak Megharaj Mallavarapu 《World journal of microbiology & biotechnology》2010,26(12):2199-2210
In order to remove heavy metals (HMs) from contaminated shrimp pond at the highest concentrations found of; 0.75 mg/l Cd2+, 62.63 mg/l Pb2+, 34.60 mg/l Cu2+ and 58.50 mg/l Zn2+, two strains of purple nonsulfur bacteria isolated from shrimp ponds (NW16 and KMS24) were investigated for their ability
to immobilize HMs in 3% NaCl in both microaerobic-light and aerobic-dark conditions. Based on metabolic inhibition and metabolic-dependent
studies, it was concluded that both strains removed HMs using biosorption and also bioaccumulation. The efficiency of removal
by both strains with both incubating conditions tested was in the order of lead (Pb) > copper (Cu) > zinc (Zn) > cadmium (Cd).
Optimal conditions for removal of HMs by strain NW16 were; cells in the log phase at 4.5 mg DCW/ml, pH 6.0, and 30°C for 30 min.
With microaerobic-light conditions, the relative percent removal of HMs was: Pb, 83; Cu, 59; Zn, 39; Cd, 23 and slightly more
with the aerobic-dark conditions (Pb, 90; Cu, 69; Zn, 46; Cd, 28). Cells in the log phase at 5.0 mg DCW/ml, pH 5.5, and 35°C
for 45 min were optimal conditions for strain KMS24 and there were no significant differences for the removal percentages
of HMs with either incubating conditions (averages: Pb, 96; Cu, 75; Zn, 46; Cd, 30). The presence of Ca2+ and Mg2+ significantly decreased the removal capacity of HMs for both strains. 相似文献
997.
998.
Han-liang Cheng Si-ping Sun Yong-xing Peng Xiao-yun Shi Xin Shen Xue-ping Meng Zhi-guo Dong 《Molecular biology reports》2010,37(6):2665-2673
A full-length cDNA coding lipoprotein lipase (LPL) was cloned from liver of adult common carp (Cyprinus carpio Var. Jian) by RT-PCR and rapid amplification of cDNA ends (RACE) approaches. The cDNA obtained was 2,411 bp long with a 1,524 bp
open reading frame (ORF) encoding 507 amino acids. This amino acid sequence contains two structural regions: N-terminus (24–354
residues) and C-terminus (355–507 residues). Before N-terminus, 1–23 residues is signal peptide, 6–23 residues is transmembrance
helix. At N-terminus, some conversed functional sites were found, including two N-linked glycosylation sites Asn41 and Asn88; one catalytic triad Ser174, Asp198 and His283; one conserved heparin-binding site Arg321 to Arg324 (RKNR); eight cysteines residues Cys69 and Cys82, Cys258 and Cys281, Cys306 and Cys325, Cys317 and Cys320 which are involved in four disulfide bridges; one polypeptide “lid” that participates in substrate specificity. At C-terminus,
Asn401 is another N-linked glycosylation site, and Trp434 and Trp435 (WW) is lipid-binding site. The amino acid sequence has a high similarity, and shows similar structural features to LPL of
other species. Tissue distribution of LPL mRNA in liver, head kidney, mesenteric adipose tissue, heart and white muscle of common carp was analyzed by semi-quantitative
RT-PCR method using β-actin gene as internal control. The result showed that the expressions of LPL mRNA were detected in all examined tissues of common carp. The expression levels of LPL in the mesenteric adipose tissue was highest among these tissues, following in liver and head kidney, and the lowest expression
was found in heart and white muscle. 相似文献
999.
Background
The task of recognizing and identifying species names in biomedical literature has recently been regarded as critical for a number of applications in text and data mining, including gene name recognition, species-specific document retrieval, and semantic enrichment of biomedical articles. 相似文献1000.
Soňa Kucharíková Patrick Van Dijck Magdaléna Lisalová Helena Bujdáková 《Central European Journal of Biology》2010,5(3):318-323
In the last decade, infections caused by Candida glabrata have become more serious, particularly due to its decreased susceptibility to azole derivatives and its ability to form biofilm.
Here we studied the resistance profile of 42 C. glabrata clinical isolates to different azoles, amphotericin B and echinocandins. This work was also focused on the ability to form
biofilm which plays a role in the development of antifungal resistance. The minimal inhibitory concentration testing to antifungal
agents was performed according to the CLSI (Clinical and Laboratory Standards Institute) M27-A3 protocol. Quantification of
biofilm was done by XTT reduction assay. All C. glabrata clinical isolates were resistant to itraconazole and sixteen also showed resistance to fluconazole. All isolates remained
susceptible to voriconazole. Amphotericin B was efficient in a concentration range of 0.125–1 mg/L. The most effective antifungal
agents were micafungin and caspofungin with the MIC100 values of ≤0.0313–0.125 mg/L. Low concentrations of these agents reduced biofilm formation as well. Our results show that
resistance of different C. glabrata strains is azole specific and therefore a single azole resistance cannot be assumed to indicate general azole resistance.
Echinocandins proved to have very high efficacy against clinical C. glabrata strains including those with ability to form biofilm. 相似文献