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81.
Paurodontella parapitica n. sp., collected from the rhizosphere of an apple tree in Kermanshah province, western Iran, is described. The new species is characterized by a body length of 505 to 723 µm (females) and 480 to 600 µm (males), lip region continuous by depression; 7 to 8 μm broad, 3 to 4 µm high, stylet length 7 to 9 µm or 1 to 1.3 times the lip region diameter, short postuterine sac of 4 to 6 μm long, lateral fields with five to six incisures; outer incisures crenated and inner incisures weakly crenated, excretory pore situated 90 to 100 µm from anterior end; functional males common in the population, with spicules 24 to 26 μm long. Tail of both sexes similar, almost straight and elongate-conoid. The new species resembles in morphology and morphometrics to four known species of the genus, namely P. apitica, P. minuta, P. myceliophaga, and P. sohailai. The results of phylogenetic analyses based on sequences of D2/D3 expansion region of 28S rRNA gene revealed this genus is polyphyletic in four different clades in Tylenchid. 相似文献
82.
The Impact of Genetic Removal of GFAP and/or Vimentin on Glutamine Levels and Transport of Glucose and Ascorbate in Astrocytes 总被引:12,自引:0,他引:12
Pekny Milos Eliasson Camilla Siushansian Ramin Ding Mei Dixon S. Jeffrey Pekna Marcela Wilson John X. Hamberger Anders 《Neurochemical research》1999,24(11):1357-1362
The importance of the intermediate filament (IF) proteins glial fibrillary acidic protein (GFAP) and vimentin for astrocyte function was studied by investigating astrocytes prepared from GFAP-/-and/or vimentin-/- mice. The rate of glucose uptake through facilitative hexose transporters was not affected by depletion of GFAP or vimentin. Similarly, the absence of these IF proteins did not affect ascorbate uptake, under control or cyclic AMP-stimulated conditions, or ascorbate efflux through volume-sensitive organic anion channels. However, compared with wild-type astrocytes, glutamine concentrations were increased up to 200% in GFAP-/- astrocytes and up to 150% in GFAP+/-astrocytes and this increase was not dependent on the presence of vimentin. GFAP-/- astrocytes in culture still contain IFs (made of vimentin and nestin), whereas GFAP-/-vim-/- cultured astrocytes lack IFs. Thus, glutamine levels appear to correlate inversely with GFAP, rather than depend on the presence of IFs per se. Furthermore, the effect of GFAP is dose-dependent since the glutamine concentration in GFAP+/- astrocytes falls between those in wild-type and GFAP-/-astrocytes. 相似文献
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84.
Behnaz Sadat Jafarzade Azam Bolhassani Seyed Mehdi Sadat Ramin Yaghobi 《International journal of peptide research and therapeutics》2017,23(1):145-153
The HIV-1 Nef protein expressed early in viral life cycle has been known as a potent candidate for therapeutic vaccine development. Due to different cell barriers, various cell penetrating peptides (CPPs) such as Pep-1 and CADY-2 have been known to deliver biologically active proteins to cytoplasmic compartments via the plasma membrane. In current study, we firstly evaluated the efficiency of lentiviral vector (pCDH-CMV-MCS-EF1-cGFP-T2A-puro) and eukaryotic expression vector (pEGFP-N1) for expression of HIV-1 Nef protein in HEK-293T cells using TurboFect transfection reagent. Our results showed that both vectors can effectively express the Nef proteins within the target cell. The pEGFP-N1 was more effective than pCDH-GFP for protein expression. Furthermore, Nef protein was expressed in E. coli as GST-Nef fusion and transfected by the amphipathic CPPs including Pep-1 and CADY-2 into HEK-293T cells. The size and morphology of the GST-Nef/CPP complexes were evaluated by scanning electron microscopy, and Zetasizer. Our data indicated that the recombinant GST-Nef protein generated in BL21 strain migrated as a clear band of ~50 kDa in SDS-PAGE. The CPP/GST-Nef nanoparticles were formed with a diameter of below 200 nm and notably delivered into HEK-293T cells. Generally, the Nef protein was expressed in prokaryotic and eukaryotic expression systems using different vectors and efficiently transfected in mammalian cells using various delivery systems. The in vitro efficient delivery of HIV-1 Nef gene and also its protein supports the potential of Nef DNA constructs and CPPs as potent carriers of Nef protein for HIV vaccine design in Future. 相似文献
85.
Vahid Jabbari Mahmoud Sowti Khiabani Reza Rezaei Mokarram Azad Mohammad Hassanzadeh Elham Ahmadi Sasan Gharenaghadeh Nayyer Karimi Hossein Samadi Kafil 《Probiotics and antimicrobial proteins》2017,9(2):189-193
The aim of this study is to isolate and identify Lactobacillus plantarum isolates from traditional cheese, Kouzeh, and evaluate their antimicrobial activity against some food pathogens. In total, 56 lactic acid bacteria were isolated by morphological and biochemical methods, 12 of which were identified as Lactobacillus plantarum by biochemical method and 11 were confirmed by molecular method. For analyzing the antimicrobial activity of these isolates properly, diffusion method was performed. The isolates were identified by 318 bp band dedicated for L. plantarum. The isolated L. plantarum represented an inhibitory activity against four of the pathogenic bacteria and showed different inhibition halos against each other. The larger halos were observed against Staphylococcus aureus and Staphylococcus epidermidis (15 ± 0.3 and 14.8 ± 0.7 mm, respectively). The inhibition halo of Escherichia coli was smaller than that of other pathogen and some L. plantarum did not show any inhibitory activity against E. coli, which were resistant to antimicrobial compounds produced by L. plantarum. The isolated L. plantarum isolates with the antimicrobial activity in this study had strong probiotic properties. These results indicated the nutritional value of Kouzeh cheese and usage of the isolated isolates as probiotic strains. 相似文献
86.
Ramin Raouf 《生物化学与生物物理学报:生物膜》2005,1669(2):135-141
To investigate fast purinergic signaling in invertebrates, we examined the functional properties of a P2X receptor subunit cloned from the parasitic platyhelminth Schistosoma mansoni. This purinoceptor (SmP2X) displays unambiguous homology of primary sequence with vertebrate P2X subunits. SmP2X subunits assemble into homomeric ATP-gated channels that exhibit slow activation kinetics and are blocked by suramin and PPADS but not TNP-ATP. SmP2X mediates the uptake of the dye YO-PRO-1 through the formation of large pores and can be blocked by submicromolar concentrations of extracellular Zn2+ ions (IC50=0.4 μM). The unique receptor phenotype defined by SmP2X suggests that slow kinetics, modulation by zinc and the ability to form large pores are ancestral properties of P2X receptors. The high sensitivity of SmP2X to zinc further reveals a zinc regulation requirement for the parasite's physiology that could potentially be exploited for therapeutic purposes. 相似文献
87.
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89.
Massah AR Adibi H Khodarahmi R Abiri R Majnooni MB Shahidi S Asadi B Mehrabi M Zolfigol MA 《Bioorganic & medicinal chemistry》2008,16(10):5465-5472
Silica sulfuric acid catalyzes efficiently the reaction of sulfonamides with both carboxylic acid anhydrides and chlorides under solvent-free and heterogeneous conditions. All the reactions were done at room temperature and the N-acylsulfonamides were obtained with high yields and purity via an easy work-up procedure. This method is attractive and is in a close agreement with green chemistry. These compounds were also investigated for antibacterial activity, including Gram-positive cocci and Gram-negative bacilli, and carbonic anhydrase II inhibitory activity. 相似文献
90.
C. Sarthou M. C. Boisselier‐Dubayle J. Lambourdire S. Samadi 《Molecular ecology resources》2003,3(2):221-223
Pitcairnia geyskesii is a saxicolous bromeliad endemic to the granitic inselbergs of French Guiana and Surinam. Seven polymorphic microsatellite markers were characterized to investigate the polymorphism among individuals sampled on five inselbergs in French Guiana. The total number of alleles per locus varied from four to 14. Mean observed heterozygosities at each microsatellite locus ranged from 0.114 to 0.629. This set of microsatellites offers an efficient tool for more detailed investigations on the genetic structure of fragmented populations living on such a singular and insular habitat within tropical rainforest. 相似文献