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91.
Jafari Marziyeh Shahsavar Ali Reza 《In vitro cellular & developmental biology. Plant》2022,58(1):155-168
In Vitro Cellular & Developmental Biology - Plant - As a novel antioxidant, sodium nitroprusside (SNP) can be used to reduce the adverse effects of various abiotic stresses, especially drought... 相似文献
92.
The two murine single-chain Fv (scFv) genes against human interleukin IL-4 and IL-6 cytokines were cloned in a plant expression vector (pGEJAE1) and mobilized to Agrobacterium tumefaciens. Tobacco leaf discs were co-cultured with Agrobacterium and transferred to selective media for regeneration. The tobacco in vitro plants produced scFvs against human IL-4 and IL-6. Only 8% of transformed plants expressing anti-IL-4 scFv were obtained versus 76% of transformed plants expressing anti-IL-6 scFv. In addition, some plants producing anti-IL-4 and anti-IL-6 scFvs aged more rapidly in in vitro conditions and in greenhouse pots than did control plants. Western blot analysis showed that the transformed Nicotiana tabacum plants contained proteins with an apparent molecular mass on electrophoresis of ca. 32 kDa, corresponding to the predicted size of the scFvs. As entire plant root seemed to accumulate more scFv than did leaves, we decided to continue working with isolated roots. Anti-IL-6 scFvs were detected in cultivated roots and their culture media. Functional anti-IL-6 scFv accounted for 0.16–0.18% of total soluble proteins. The affinity of the anti-IL-6 scFv produced in plants and measured by Biacore was similar to that of scFv produced in Escherichia coli. The high levels of antibody accumulation in isolated roots and secretion into the medium demonstrate the potential for producing recombinant protein in bioreactor systems.these authors contributed equally to this workthese authors contributed equally to this work 相似文献
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Jafari Marjan Shiran Behrouz Rabiei Gholamreza Ravash Rudabeh Sayed Tabatabaei Badraldin Ebrahim Martínez-García Pedro J. Martínez-Gómez Pedro 《Plant Growth Regulation》2022,97(2):357-373
Plant Growth Regulation - Almond is a stone fruit crop belonging to the Rosaceae family, cultivated in the temperate region of the world for its high nutritive valued fruits. In today’s... 相似文献
96.
H Hong L Xu J Liu WD Jones Z Su B Ning R Perkins W Ge K Miclaus L Zhang K Park B Green T Han H Fang CG Lambert SC Vega SM Lin N Jafari W Czika RD Wolfinger F Goodsaid W Tong L Shi 《PloS one》2012,7(9):e44483
During the last several years, high-density genotyping SNP arrays have facilitated genome-wide association studies (GWAS) that successfully identified common genetic variants associated with a variety of phenotypes. However, each of the identified genetic variants only explains a very small fraction of the underlying genetic contribution to the studied phenotypic trait. Moreover, discordance observed in results between independent GWAS indicates the potential for Type I and II errors. High reliability of genotyping technology is needed to have confidence in using SNP data and interpreting GWAS results. Therefore, reproducibility of two widely genotyping technology platforms from Affymetrix and Illumina was assessed by analyzing four technical replicates from each of the six individuals in five laboratories. Genotype concordance of 99.40% to 99.87% within a laboratory for the sample platform, 98.59% to 99.86% across laboratories for the same platform, and 98.80% across genotyping platforms was observed. Moreover, arrays with low quality data were detected when comparing genotyping data from technical replicates, but they could not be detected according to venders' quality control (QC) suggestions. Our results demonstrated the technical reliability of currently available genotyping platforms but also indicated the importance of incorporating some technical replicates for genotyping QC in order to improve the reliability of GWAS results. The impact of discordant genotypes on association analysis results was simulated and could explain, at least in part, the irreproducibility of some GWAS findings when the effect size (i.e. the odds ratio) and the minor allele frequencies are low. 相似文献
97.
OBJECTIVE: To determine the risk of high-grade squamous intraepithelial lesion (HSIL)/cervical intraepithelial neoplasia (CIN) 2 or 3 in perimenopausal and postmenopausal women with high-risk human papillomavirus (HPV) DNA-positive atypical squamous cells of undetermined significance (ASCUS) on Pap tests. STUDY DESIGN: A total of 752 perimenopausal and postmenopausal women (patients 45 years) with an ASCUS interpretation on ThinPrep Pap tests were identified in 2002 and 2003. High risk HPVDNA was detected in 191 (25.4%) women. The follow-up results in these 136 women were compared with those of women <45 years. RESULTS: Of the 136 perimenopausal and postmenopausal women, 64.7% became negative on cytology or biopsy and 30.9% revealed persistent low-grade SIL (LSIL)/CIN 1. Furthermore, 5 women (3.68%) were diagnosed with HSIL/CIN 2 or 3, and 1 patient had squamous cell carcinoma (0.74%). The rate of HSIL/CIN 2 or 3 or worse detected in perimenopausal and postmenopausal women was significant lower than 10.6% in women <45 years (p = 0.028). CONCLUSION: Our study showed that perimenopausal and postmenopausal women with high-risk HPV positivity and an ASCUS interpretation have a significantly lower risk of HSIL/CIN 2 or 3 detected. Nonetheless, the risk of a significant finding on workup, including invasive carcinoma, indicates the need for colposcopic evaluation of these women. 相似文献
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This study was designed to shed more light onto the three different brainstem regions which are implicated in the pain pathway
for the level of various excitatory and inhibitory neurotransmitters before and following neuronal stimulation. The in vivo
microdialysis technique was used in awake, freely moving adult Sprague-Dawley rats. The neurotransmitters studied included
aspartate, glutamate, GABA, glycine, and taurine. The three brainstem regions examined included the mid-brain periaqueductal
gray (PAG), the medullary nucleus raphe magnus (NRM), and the spinal trigeminal nucleus (STN). Neuronal stimulation was achieved
following the administration of the sodium channel activator veratridine. The highest baseline levels of glutamate (P < 0.0001), aspartate (P < 0.0001), GABA (P < 0.01), taurine (P < 0.0001), and glycine (P < 0.001) were seen in the NRM. On the other hand, the lowest baseline levels of glutamate, GABA, glycine, and taurine were
found in the PAG, while that of aspartate was found in the STN. Following the administration of veratridine, the highest release
of the above neurotransmitters except for the aspartate and glycine was found in the PAG where the level of glutamate increased
by 1,310 ± 293% (P < 0.001), taurine by 1,008 ± 143% (P < 0.01), and GABA by 10,358 ± 1,920% (P < 0.0001) when comparison was performed among the three brainstem regions and in relation to the baseline levels. The highest
release of aspartate was seen in the STN (2,357 ± 1,060%, P < 0.001), while no significant difference was associated with glycine. On the other hand, the lowest release of GABA and
taurine was found in the STN (696 ± 91 and 305 ± 25%, respectively), and glutamate and aspartate in the NRM (558 ± 200 and
874 ± 315%, respectively). Our results indicate, and for the first time, that although some differences are seen in the baseline
levels of the above neurotransmitters in the three regions studied, there are quite striking variations in the level of release
of these neurotransmitters following neuronal stimulation in these regions. In our opinion this is the first study to describe
the pain activation/modulation related changes of the excitatory and inhibitory amino acids profile of the three different
brainstem areas. 相似文献
99.
Summary The Warburg's manometric technique was used to measure the rate of oxygen consumption of the second generation of laboratory-reared snails, Biomphalaria alexandrina and Bulinus truncatus at two temperatures of 25° and 30°C. The individual weight of the experimental snails ranged between 40 and 78 mg for B. alexandrina, between 60 and 90 mg for B. truncatus.At 25°C, the uninfected snails B. alexandrina consumed oxygen at an average rate of 0.096 ± 0.020 ml/g wet wt/hr. The rate of oxygen consumption increased to an average of 0.147 ± 0.008 ml/g wet wt/hr for uninfected snails maintained at 30°C (about 53 per cent increase). The average RW value for uninfected snails maintained at 25°C was 0.80.The snail Bulinus truncatus showed higher oxygen requirements than the snail Biomphalaria alexandrina. At 25°C, it consumed oxygen at an average rate of 0.124 ± 0.016 ml/g wet wt/hr. At 30°C, the rate of oxygen consumption reached a value of 0.220 + 0.006 ml/g wet wt/hr. The average RQ for Bulinus truncatus maintained at 25°C was 0.87.The rate of oxygen consumption of the schistosome — infected Biomphalaria alexandrina snails, maintained at 25°C decreased to an average rate of 0.059 ± 0.010 ml/g wet wt/hr, (an average of 39 per cent decrease). The respiratory quotient (RQ) also decreased to an average value of 0.58. Further research is suggested to clarify the metabolism of both schistosome-infected and uninfected snails.Read at the Ist African Symposium on Bilharziasis, Cairo Egypt, U.A.R., February, 1969.From the Laboratory of Bilharziasis Research, National Research Centre, Dokki, Egypt, U.A.R. 相似文献
100.
Habib T. Abul Adnan T. Abul Eman A. Al-Athary Abdulla E. Behbehani Mousa E. Khadadah Hussein M. Dashti 《Molecular and cellular biochemistry》1995,148(2):139-145
In vertebrate retina, rod outer segment is the site of visual transduction. The inward cationic current in the dark-adapted outer segment is regulated by cyclic GMP. A light flash on the outer segment activates a cyclic GMP phosphodiesterase resulting in rapid hydrolysis of the cyclic nucleotide which in turn causes a decrease in the dark current. Restoration of the dark current requires inactivation of the phosphodiesterase and synthesis of cyclic GMP. The latter is accomplished by the enzyme guanylate cyclase which catalyzes the formation of cyclic GMP from GTP. Therefore, factors regulating the cyclase activity play a critcal role in visual transduction. But regulation of the cyclase by some of these factors — phosphodiesterase, ATP, the soluble proteins and metal cofactors (Mg and Mn) — is controversial. The availability of different types of cyclase preparations, dark-adapted rod outer segments with fully inhibited phosphodiesterase activity, partially purified cyclase without PDE contamination, cloned rod outer segment cyclase free of other rod outer segment proteins, permitted us to address these controversial issues. The results show that ATP inhibits the basal cyclase activity but enhances the stimulation of the enzyme by soluble activator, that cyclase can be activated in the dark at low calcium concentrations under conditions where phosphodiesterase activity is fully suppressed, and that greater activity is observed with manganese as cofactor than magnesium. These results provide a better understanding of the controls on cyclase activity in rod outer segments and suggest how regulation of this cyclase by ATP differs from that of other known membrane guanylate cyclases.This work was supported by the grants from the National Institutes of Health (EY07158, EY 05230, EY 10828, NS 23744) and the equipment grant from Pennsylvania Lions Eye Research Foundation. 相似文献