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161.
Cai X Davis EJ Ballif J Liang M Bushman E Haroldsen V Torabinejad J Wu Y 《Journal of experimental botany》2006,57(11):2563-2569
Laccases, EC 1.10.3.2 or p-diphenol:dioxygen oxidoreductases, are multi-copper containing glycoproteins. Despite many years of research, genetic evidence for the roles of laccases in plants is mostly lacking. In this study, a reverse genetics approach was taken to identify T-DNA insertional mutants (the SALK collection) available for genes in the Arabidopsis laccase family. Twenty true null mutants were confirmed for 12 laccase genes of the 17 total laccase genes (AtLAC1 to AtLAC17) in the family. By examining the mutants identified, it was found that four mutants, representing mutations in three laccase genes, showed altered phenotypes. Mutants for AtLAC2, lac2, showed compromised root elongation under PEG-induced dehydration conditions; lac8 flowered earlier than wild-type plants, and lac15 showed an altered seed colour. The diverse phenotypes suggest that laccases perform different functions in plants and are not as genetically redundant as previously thought. These mutants will prove to be valuable resources for understanding laccase functions in vivo. 相似文献
162.
Cochlosoma sp. infection was identified in a single case among 60 stunted diarrheic native turkey poults, Meleagris galopavo. A large number of the flagellated parasites was found free or within the intervillous spaces of the jejunum, ileum and cecum. Moderate enteritis was associated with the parasites. In TEM studies of the parasagittal sections of the parasite, a prominent ventral sucker like disc and flagella emerging from an opening on the ventrodorsal surface of the pyriform uninuclear parasite were found. The morphological characteristics of this protozoan match with those described for Cochlosoma anatis. The parasite could be considered as an intestinal pathogenic protozoan causing stunting and diarrhea in turkeys in Iran. 相似文献
163.
Seyyed Javad Sabounchei Hassan Nemattalab Sima Khani Harry Adams 《Inorganica chimica acta》2009,362(1):105-2492
The reactions of phosphorus ylide (p-tolyl)3PCHC(O)CH3 (Y1) with HgX2 (X = Cl and Br) and (p-tolyl)3PCHC(O)C6H4NO2 (Y2) with HgX2 (X = Cl, Br and I) in equimolar ratios using methanol as a solvent are reported. These reactions led to binuclear complexes. C-Coordination of ylides and trans-like structure of complexes [(Y1) · HgBr2]2 and [(Y2) · HgBr2]2 · 2DMSO are demonstrated by single crystal X-ray analyses. The IR, 1H, 13C and 31P NMR data for the other synthesized compounds are similar to the latter complexes, indicating similar structures. Elemental analyses indicate a 1:1 stoichiometry between the ylide and Hg(II) halide in all the products. The ab initio studies indicated that for all dimeric compounds, the observed trans-like structures are 7-10 kcal/mol more stable than the alternative possible cis-like isomers. Although the calculated bond lengths are slightly longer than the measured ones, the similarity of calculated and measured bond angles reflects the similar geometrical structures for these compounds in both the solid state and the gas phase. 相似文献
164.
Embryoid bodies (EBs) are primitive embryonic structures derived from differentiating embryonic stem cells (ESCs). Many techniques
have been used to obtain EBs. Improving the technique of EB formation can help in achieving better results in ESCs differentiation
into neurons, myocardiocytes, haemopoeitic cells, and others. We evaluated the use of Sigmacote™ as a hydrophobic substrate
to improve EB formation. CCE and P19 cell lines were used to obtain EBs and retinoic acid was used to induce neural differentiation.
The results revealed that Sigmacote™, as a hydrophobic substrate, can improve EB formation from ESCs. Our results demonstrate
that the silicon-coating of glass petri dishes by Sigmacote™ is an easy and reproducible technique to enhance EB formation
from murine ESCs and EC cells. 相似文献
165.
A total of 370 specimens of Paracobitis malapterura in the Zarrin-Gol River (east of the Elburz Mts, Iran) were caught by regular monthly collection throughout one year from
November 2006 to October 2007. The specimens were then examined for age and growth, reproduction and feeding attributes. Based
on otolith readings the maximum ages of the population observed were 3+ years for males and 4+ years for females. The specimens ranged in size from 38 to 130 mm total length, weighing from 0.68 to 30.55 g total weight.
Length-weight relationship was estimated as W = 0.020L
2.62 for males, W = 0.002L
3.81 for females and W = 0.008L
3.08 for the population. Sex ratio was 1: 1.27 in favor of females. The Gonadosomatic index indicated that reproduction of the
loach in the river occurred around April–May, with the highest average value of 1.48 for males and of 5.36 for females in
May. The absolute fecundity ranged between 92–1180 eggs with a mean of 456.31 eggs. Diameter of oocytes ranged from 0.11 to
2.80 mm with a mean value of 0.95 mm. The absolute fecundity and oocyte diameter to fish size (length and weight) and age
were not significantly correlated. Plecoptera and Trichoptera dominated the diet contents composing 72.43% and 20.80% of total
frequency of food items, respectively. 相似文献
166.
167.
Seyed Javad Davarpanah Seo Hee Jung Yaw Joo Kim Youn-Il Park Sung Ran Min Jang Ryol Liu Won Joong Jeong 《Journal of Plant Biology》2009,52(3):244-250
Plastids from Nicotiana benthamiana were transformed with the vector for dicistronic expression of two genes—aminoglycoside 3'-adenyltransferase (aadA) and green fluorescent protein (gfp)—in the plastids of Nicotiana tabacum. Transplastomic shoots exhibited green fluorescence under UV light. Transformation efficiencies were similar between species.
Although the border sequence (trnI and trnA) for homologous recombination to transform the plastid genome of N. benthamiana was identical to that sequence of N. tabacum, the exception was a 9-bp addition in the intron of trnI. This indicated that the N. tabacum sequence used as a border region for recombination was sufficient to insert the foreign gene into the target site between
the trnI and trnA of N. benthamiana with similar efficiency. Southern blot analysis detected the presence of aadA and gfp between trnI and trnA in the plastid genome of N. benthamiana. Northern and western blot analyses revealed high expression of gfp in the plastids from petals and leaves. Our results suggest that the plastid transformation system established here is applicable
to investigations of the interactions between plastid and nucleus in N. benthamiana. 相似文献
168.
Knowledge of the lethal and sublethal effects of pesticides on biological control agents is necessary for successful implementation of integrated pest management programs. The sublethal effect of acaricide fenpyroximate (Ortus®) on performance of females and their offspring of Phytoseius plumifer (Canestrini &; Fanzago), an efficient predator of Tetranychus urticae Koch, was determined under laboratory conditions. The adult predators were exposed to the residues of the acaricide on fig leaves and the LC50 value was determined based on a concentration–response analysis. The results showed that sublethal concentrations of fenpyroximate significantly affected the fecundity and longevity of the treated females of P. plumifer. Reproductive and life table parameters of the subsequent generation were also affected by sublethal concentrations. It could be concluded that sublethal concentrations can significantly reduce the population growth of P. plumifer and this should be considered in integrated pest management programs. 相似文献
169.
Ali Yilmaz Nils T. Nyberg Per Mølgaard Javad Asili Jerzy W. Jaroszewski 《Metabolomics : Official journal of the Metabolomic Society》2010,6(4):511-517
The aim of this study was to explore feasibility of 1H NMR metabolic fingerprinting for discrimination of authenticity of saffron using principal component analysis (PCA) modeling.
Authentic reference Iranian saffron (n = 31) and commercial samples (n = 32) were used. Cross-validated PCA models based on 1H NMR spectra of solutions prepared by direct extraction of grinded saffron with methanol-d
4 distinguished reference Iranian saffron samples from commercial samples that formed several distinct clusters, some of which
represent falsified samples as confirmed by microscopic analysis. The production sites and drying conditions of the authentic
reference Iranian samples were not reflected in the current dataset. Picrocrocin and glycosyl esters of crocetin emerged as
the most important 1H NMR markers of authentic saffron by using statistical correlation spectroscopy. In conclusion, 1H NMR spectra of saffron extracts combined with pattern recognition by PCA provide immediate means of unsupervised classification
of saffron samples. 相似文献
170.
Warfield KL Swenson DL Olinger GG Nichols DK Pratt WD Blouch R Stein DA Aman MJ Iversen PL Bavari S 《PLoS pathogens》2006,2(1):e1
The filoviruses Marburg virus and Ebola virus (EBOV) quickly outpace host immune responses and cause hemorrhagic fever, resulting in case fatality rates as high as 90% in humans and nearly 100% in nonhuman primates. The development of an effective therapeutic for EBOV is a daunting public health challenge and is hampered by a paucity of knowledge regarding filovirus pathogenesis. This report describes a successful strategy for interfering with EBOV infection using antisense phosphorodiamidate morpholino oligomers (PMOs). A combination of EBOV-specific PMOs targeting sequences of viral mRNAs for the viral proteins (VPs) VP24, VP35, and RNA polymerase L protected rodents in both pre- and post-exposure therapeutic regimens. In a prophylactic proof-of-principal trial, the PMOs also protected 75% of rhesus macaques from lethal EBOV infection. The work described here may contribute to development of designer, "druggable" countermeasures for filoviruses and other microbial pathogens. 相似文献