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71.
72.
Seyedeh Maryam Banihashemian Vengadesh Periasamy Goh Boon Tong Saadah Abdul Rahman 《PloS one》2016,11(3)
Studying the effect of a magnetic field on oligonucleotide DNA can provide a novel DNA manipulation technique for potential application in bioengineering and medicine. In this work, the optical and electrochemical response of a 100 bases oligonucleotides DNA, cytosine-guanine (CG100), is investigated via exposure to different magnetic fields (250, 500, 750, and 1000 mT). As a result of the optical response of CG100 to the magnetic field, the ultra-violet-visible spectrum indicated a slight variation in the band gap of CG100 of about 0.3 eV. Raman spectroscopy showed a significant deviation in hydrogen and phosphate bonds’ vibration after exposure to the magnetic field. Oligonucleotide DNA mobility was investigated in the external electric field using the gel electrophoresis technique, which revealed a small decrease in the migration of CG100 after exposure to the magnetic field. 相似文献
73.
Field-scale environmental models have been widely used in aquatic exposure assessments of pesticides. Those models usually require a large set of input parameters and separate simulations for each pesticide in evaluation. In this study, a simple use-exposure relationship is developed based on regression analysis of stochastic simulation results generated from the Pesticide Root-Zone Model (PRZM). The developed mathematical relationship estimates edge-of-field peak concentrations of pesticides from aerobic soil metabolism half-life (AERO), organic carbon-normalized soil sorption coefficient (KOC), and application rate (RATE). In a case study of California crop scenarios, the relationships explained 90-95% of the variances in the peak concentrations of dissolved pesticides as predicted by PRZM simulations for a 30-year period. KOC was identified as the governing parameter in determining the relative magnitudes of pesticide exposures in a given crop scenario. The results of model application also indicated that the effects of chemical fate processes such as partitioning and degradation on pesticide exposure were similar among crop scenarios, while the cross-scenario variations were mainly associated with the landscape characteristics, such as organic carbon contents and curve numbers. With a minimum set of input data, the use-exposure relationships proposed in this study could be used in screening procedures for potential water quality impacts from the off-site movement of pesticides. 相似文献
74.
Alternative splicing is a main component of protein diversity, and aberrant splicing is known to be one of the main causes of genetic disorders such as cancer. Many statistical and computational approaches have identified several major factors that determine the splicing event, such as exon/intron length, splice site strength, and density of splicing enhancers or silencers. These factors may be correlated with one another and thus result in a specific type of splicing, but there has not been a systematic approach to extracting comprehensible association patterns. Here, we attempted to understand the decision making process of the learning machine on intron retention event. We adopted a hybrid learning machine approach using a random forest and association rule mining algorithm to determine the governing factors of intron retention events and their combined effect on decision-making processes. By quantifying all candidate features into five category values, we enhanced the understandability of generated rules. The interesting features found by the random forest algorithm are that only the adenine- and thymine-based triplets such as ATA, TTA, and ATT, but not the known intronic splicing enhancer GGG triplet is shown the significant features. The rules generated by the association rule mining algorithm also show that constitutive introns are generally characterized by high adenine- and thymine-based triplet frequency (level 3 and above), 3' and 5' splice site scores, exonic splicing silencer scores, and intron length, whereas retained introns are characterized by low-level counterpart scores. 相似文献
75.
76.
Polymer conjugation increases an enzyme's circulation time and stability for use as a therapeutic agent, but this attachment indubitably affects its properties. Covalent attachment of multiple polyethylene glycol chains with sizes of either 2, 5, 10, or 20 kDa increases the molecular weight and hydrodynamic radius of the model enzyme trypsin. The sizes of these polymer-enzyme conjugates are increased to be within the recommended limits for PDEPT applications. The T(d) increases from 49 to 60 °C to expand the enzyme's workable range of conditions. This functionalization with PEG polymers of varying lengths maintains trypsin's enzymatic activity. Conjugate activities are 79-120% that of native trypsin at room temperature and 221-432% that of trypsin at 37 °C. 相似文献
77.
A note on heat shock protein 70 expression in goats subjected to road transportation under hot, humid tropical conditions 总被引:1,自引:0,他引:1
Zulkifli I Norbaiyah B Cheah YW Soleimani AF Sazili AQ Goh YM Rajion MA 《Animal : an international journal of animal bioscience》2010,4(6):973-976
The influence of two different stocking densities (0.20 m2/animal and 0.40 m2/animal) in transit under the hot, humid tropical conditions on heat shock protein (hsp) 70 induction was investigated in 60 Boer does. The animals were road transported for 3 h and the control group was kept under normal conditions in the farm. Irrespective of stocking density, transportation significantly increased hsp 70 densities (P < 0.05) in the kidneys. The hsp 70 response in the kidneys was more profound compared with those of heart tissues. Higher stocking density was more stressful to the goats based on hsp 70 expression. These results suggest that, irrespective of stocking density, transportation under hot, humid tropical conditions evoked hsp 70 reactions. 相似文献
78.
Patel NS Nandra KK Brines M Collino M Wong WF Kapoor A Benetti E Goh FY Fantozzi R Cerami A Thiemermann C 《Molecular medicine (Cambridge, Mass.)》2011,17(9-10):883-892
Recent studies have shown that erythropoietin, critical for the differentiation and survival of erythrocytes, has cytoprotective effects in a wide variety of tissues, including the kidney and lung. However, erythropoietin has been shown to have a serious side effect-an increase in thrombovascular effects. We investigated whether pyroglutamate helix B-surface peptide (pHBSP), a nonerythropoietic tissue-protective peptide mimicking the 3D structure of erythropoietin, protects against the organ injury/ dysfunction and inflammation in rats subjected to severe hemorrhagic shock (HS). Mean arterial blood pressure was reduced to 35 ± 5 mmHg for 90 min followed by resuscitation with 20 mL/kg Ringer Lactate for 10 min and 50% of the shed blood for 50 min. Rats were euthanized 4 h after the onset of resuscitation. pHBSP was administered 30 min or 60 min into resuscitation. HS resulted in significant organ injury/dysfunction (renal, hepatic, pancreas, neuromuscular, lung) and inflammation (lung). In rats subjected to HS, pHBSP significantly attenuated (i) organ injury/dysfunction (renal, hepatic, pancreas, neuromuscular, lung) and inflammation (lung), (ii) increased the phosphorylation of Akt, glycogen synthase kinase-3β and endothelial nitric oxide synthase, (iii) attenuated the activation of nuclear factor (NF)-κB and (iv) attenuated the increase in p38 and extracellular signal-regulated kinase (ERK)1/2 phosphorylation. pHBSP protects against multiple organ injury/dysfunction and inflammation caused by severe hemorrhagic shock by a mechanism that may involve activation of Akt and endothelial nitric oxide synthase, and inhibition of glycogen synthase kinase-3β and NF-κB. 相似文献
79.
Rice blast, caused by the pathogen Magnaporthe oryzae, is a serious hindrance to rice production and has emerged as an important model for the characterization of molecular mechanisms relevant to pathogenic development in plants. Similar to other pathogenic fungi, conidiation plays a central role in initiation of M.oryzae infection and spread over a large area. However, relatively little is known regarding the molecular mechanisms that underlie conidiation in M. oryzae. To better characterize these mechanisms, we identified a conidiation-defective mutant, ATMT0225B6 (MoCDC15(T-DNA)), in which a T-DNA insertion disrupted a gene that encodes a homolog of fission yeast cdc15, and generated a second strain containing a disruption in the same allele (ΔMoCDC15(T-DNA)). The cdc15 gene has been shown to act as a coordinator of the cell cycle in yeast. Functional analysis of the MoCDC15(T-DNA) and ΔMoCDC15(T-DNA) mutants revealed that MoCDC15 is required for conidiation, preinfection development and pathogenicity in M. oryzae. Conidia from these mutants were viable, but failed to adhere to hydrophobic surface, a crucial step required for subsequent pathogenic development. All phenotypic defects observed in mutants were rescued in a strain complemented with wild type MoCDC15. Together, these data indicate that MoCDC15 functions as a coordinator of several biological processes important for pathogenic development in M. oryzae. 相似文献
80.
Phase diagrams of ternary lipid mixtures containing cholesterol have provided valuable insight into cell membrane behaviors, especially by describing regions of coexisting liquid-disordered (Ld) and liquid-ordered (Lo) phases. Fluorescence microscopy imaging of giant unilamellar vesicles has greatly assisted the determination of phase behavior in these systems. However, the requirement for optically resolved Ld + Lo domains can lead to the incorrect inference that in lipid-only mixtures, Ld + Lo domain coexistence generally shows macroscopic domains. Here we show this inference is incorrect for the low melting temperature phosphatidylcholines abundant in mammalian plasma membranes. By use of high compositional resolution Förster resonance energy transfer measurements, together with electron spin resonance data and spectral simulation, we find that ternary mixtures of DSPC and cholesterol together with either POPC or SOPC, do indeed have regions of Ld + Lo coexistence. However, phase domains are much smaller than the optical resolution limit, likely on the order of the Förster distance for energy transfer (R0, ∼2-8 nm). 相似文献