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171.
Parisa Bahmani Raheleh Halabian Mehdi Rouhbakhsh Amaneh Mohammadi Roushandeh Nasser Masroori Majid Ebrahimi Ali Samadikuchaksaraei Mohammad Ali Shokrgozar Mehryar Habibi Roudkenar 《Cell stress & chaperones》2010,15(4):395-403
Lipocalin-2 (Lcn2, NGAL) is a member of the lipocalin super family with diverse function such as the induction of apoptosis,
the suppression of bacterial growth, and modulation of inflammatory response. Much interest has recently been focused on the
physiological/pathological role of the lipocalin-2 that is considered to be a novel protective factor against oxidative stress.
However, its precise biological roles in this protection are not fully understood. In this report we intended to test the
effect of lipocalin-2 on the expression of heme oxygenase (1, 2) and superoxide dismutase (1, 2) which are two strong antioxidants. NGAL was cloned to pcDNA3.1 plasmid by using genetic engineering method. The recombinant
vector was transfected to CHO and HEK293T to establish stable cell expressing NGAL and the expression of HO-1, 2 and SOD1, 2 were compared with appropriate controls by RT-PCR and western blot. On the other hand, expression of NGAL was suppressed
by siRNA transfection in order to study the effect of lipocalin-2 on mentioned genes/proteins. The results showed that the
expression of HO-1 and SOD1, 2 enzymes were higher in cells expressing recombinant lipocalin-2 compared with the control cells. Although the expression
of HO-1 was lower in NGAL silencing cells, the expression of SOD1 and SOD2 were higher. Our data suggest that NGAL is a potent inducer of HO-1 and somewhat SOD1 and SOD2 and it appears that part of antioxidant property of NGAL could be attributed to the induction of HO-1and SOD1, 2. 相似文献
172.
He-Long Jiang Abdul Majid Maszenan Zhi-Wei Zhao Joo-Hwa Tay 《Journal of industrial microbiology & biotechnology》2010,37(3):253-262
The physical structure and activity of aerobic granules, and the succession of bacterial community within aerobic granules
under constant operational conditions and shock loading were investigated in one sequencing batch reactor over ten months.
While the maturation phase of the granulation process began on day 30, the structure of microbial community changed markedly
until after three months of reactor operation under constant conditions with a loading rate of 1.5 g phenol L−1 day−1. A shock loading of 6.0 g phenol L−1 day−1 from days 182–192 led to divergence of bacterial community, an inhibition of the biomass activity, and a decrease in phenol
removal rate in the reactor. However, phenol was still completely removed under this disturbance. After the shock loading,
the mean sizes of aerobic granules increased, and the activity of the microbial population within the granules decreased,
although there appeared highly resilient for the dominant bacterial community of aerobic granules which mainly included β-Proteobacteria.
Correlation analysis suggested that biomass concentration and biomass loading were significantly related to the community
composition of aerobic granules during the whole operational period. The development of a relatively stable bacterial community
in aerobic granules implied that those distinct dominant microbes in aerobic granules were favorably selected and proliferated
under the operational conditions. 相似文献
173.
Background
HIV-1 targets human cells expressing both the CD4 receptor, which binds the viral envelope glycoprotein gp120, as well as either the CCR5 (R5) or CXCR4 (X4) co-receptors, which interact primarily with the third hypervariable loop (V3 loop) of gp120. Determination of HIV-1 affinity for either the R5 or X4 co-receptor on host cells facilitates the inclusion of co-receptor antagonists as a part of patient treatment strategies. A dataset of 1193 distinct gp120 V3 loop peptide sequences (989 R5-utilizing, 204 X4-capable) is utilized to train predictive classifiers based on implementations of random forest, support vector machine, boosted decision tree, and neural network machine learning algorithms. An in silico mutagenesis procedure employing multibody statistical potentials, computational geometry, and threading of variant V3 sequences onto an experimental structure, is used to generate a feature vector representation for each variant whose components measure environmental perturbations at corresponding structural positions. 相似文献174.
James A Nicholls Pablo Fuentes-Utrilla Alexander Hayward George Melika György Csóka José-Luis Nieves-Aldrey Juli Pujade-Villar Majid Tavakoli Karsten Schönrogge Graham N Stone 《BMC evolutionary biology》2010,10(1):322
Background
Biological invasions provide a window on the process of community assembly. In particular, tracking natural enemy recruitment to invading hosts can reveal the relative roles of co-evolution (including local adaptation) and ecological sorting. We use molecular data to examine colonisation of northern Europe by the parasitoid Megastigmus stigmatizans following invasions of its herbivorous oak gallwasp hosts from the Balkans. Local host adaptation predicts that invading gallwasp populations will have been tracked primarily by sympatric Balkan populations of M. stigmatizans (Host Pursuit Hypothesis). Alternatively, ecological sorting allows parasitoid recruitment from geographically distinct populations with no recent experience of the invading hosts (Host Shift Hypothesis). Finally, we test for long-term persistence of parasitoids introduced via human trade of their hosts' galls (Introduction Hypothesis). 相似文献175.
Moghadam M Nasr-Esfahani M Tangestaninejad S Mirkhani V 《Bioorganic & medicinal chemistry letters》2006,16(7):2026-2030
Mild and efficient oxidation of Hantzsch 1,4-dihydropyridines with sodium periodate catalyzed by Mn(TTP)Cl supported on polystyrene-bound imidazole is reported. This heterogeneous catalyst is of great stability and reusability in the oxidation of 1,4-dihydropyridines with sodium periodate without significant loss of its catalytic activity. 相似文献
176.
177.
178.
Ebrahim Eskandari-Nasab Seyed-Shahab-adin Hasani Majid Naderi Simin Sadeghi-Bojd Mohsen Taheri 《Nucleosides, nucleotides & nucleic acids》2017,36(3):170-180
We examined the possible relationship between three RAGE polymorphisms, ?429C/T, ?374 T/A, and 63-bp deletion, and susceptibility to childhood acute lymphoblastic leukemia (ALL) in an Iranian population. This study included 75 ALL patients and 115 healthy subjects. Genotyping was performed using HEXA-ARMS-polymerase chain reaction. We found no significant association among RAGE gene polymorphisms and the risk for ALL at genotype, allelic and haplotype levels (P > 0.05). The hemoglobin levels were higher in patients with RAGE ?374 TT than in the TA carriers (P = 0.019). Our results demonstrated that the RAGE gene variations were not associated with risk of pediatrics ALL. 相似文献
179.
Sofia Karabatsos Nicholas C. Larter Danny G. Allaire Kayla Eykelboom Cesar Estevo Majid Iravani Isabel C. Barrio David S. Hik 《The Journal of wildlife management》2024,88(3):e22536
Across most of their native North American range, the horns of mountain sheep (Ovis spp.) males are getting smaller, a pattern attributed to selective hunting pressure. We measured the horns of 755 Dall's sheep males (Ovis dalli dalli) in the southern Mackenzie Mountains, Northwest Territories, between 2002 and 2017. For each male, we measured the circumference and length of each annulus for the right horn and calculated horn volume for each year. We examined changes in horn size in 4 different outfitter areas, using age at harvest as a covariate. Hunting pressure across years in the study area was consistently low, and this population did not experience the decline in horn size observed in several other mountain sheep populations in Canada. Over the 16-year period, the average horn volume of harvested males was stable and even increased in 1 outfitter area. Local management of Dall's sheep delivered independently by the guide outfitters in the Mackenzie Mountains appears to contribute to maintaining a population of males that has not been adversely affected by strong selective hunting pressure. The resilience of this management strategy may be challenged by environmental changes associated with rapid warming in northern mountain environments. 相似文献
180.
Jafarian V Sariri R Hosseinkhani S Aghamaali MR Sajedi RH Taghdir M Hassannia S 《Biochemical and biophysical research communications》2011,413(2):164-170
Up to now, all reported Ca2+-regulated photoproteins, except for mnemiopsin, have been cloned and expressed in Escherichia coli. In this study, the cDNA for an isotype of mnemiopsin, from the ctenophore Mnemiopsis leidyi, has been cloned, sequenced, and functionally expressed. The full length cDNA encoding mnemiopsin of M. leidyi was 624 bp open reading frame encoding a protein of 207 amino acid residues with calculated molecular mass of ∼24 kDa. The deduced amino acid sequence showed 90% and 84% identity to berovine (from ctenophore Beroe abyssicola) and bolinopsin 2 (from the ctenophore Bolinopsis infundibulum) respectively. In contrast to all known EF-hand in photoproteins, a unique EF-hand motif was found in mnemiopsin, in which a conserved glycine is substituted with glutamic acid. According to the results, the optimum pH was 9.0, time course of regeneration was 15 h and its Ca2+ sensitivity was lower than aequorin. Results of pKa calculation for ionizable residues, motif scan and hydrophobic interactions of cavity aromatic residues of mnemiopsin in comparison with aequorin showed different patterns in these two photoproteins. In addition, experimental results are confirmed with the theoretical studies. 相似文献