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61.
Lucifer Yellow (LYCH) and carboxyfluorescein (CF) served in Medicago truncatula roots and root nodules as the markers of apoplastic and symplastic transport, respectively. The aim of this study was to understand better the water and photoassimilate translocation pathways to and within nodules. The present study shows that in damaged roots LYCH moves apoplastically through the vascular elements but it was not detected within the nodule vascular bundles. In intact roots, the outer cortex was strongly labeled but the dye was not present in the interior of intact root nodules. The inwards movement of LYCH was halted in the endodermis. When the dye was introduced into a damaged nodule by infiltration, it spread only in the cell walls and the intercellular spaces up to the inner cortex. Our research showed that in addition to the outer cortex, the inner tissue containing bacteroid-infected cells is also an apoplastic domain. Our results are consistent with the hypothesis that nodules do not receive water from the xylem but get it and photoassimilates from phloem. A comparison between using LYCH and LYCH followed by glutaraldehyde fixation indicates that glutaraldehyde is responsible for fluorescence of some organelles within root nodule cells. The influence of the fixation on nodule fluorescence has not been reported before but must be taken into consideration to avoid errors. An attempt was made to follow carboxyfluorescein (6(5) CF) translocation from leaflets into roots and root nodules. In root nodules, CF was present in all or a couple of vascular bundles (VB), vascular endodermis and some adjacent cells. The leakage of CF from the VBs was observed, which suggests symplastic continuity between the VBs and the nodule parenchyma. The lack of CF in inner tissue was observed. Therefore, photoassimilate entry to the infected region of nodule must involve an apoplastic pathway. 相似文献
62.
P. Mark Hogarth Margaret L. Hibbs Lisa Bonadonna Bernadette M. Scott Ewa Witort Geoffrey A. Pietersz Ian F. C. McKenzie 《Immunogenetics》1987,26(3):161-168
A cDNA clone encoding the mouse Ly-17+ Fc receptor for IgG, isolated from a myelomonocytic cell line, was sequenced and expression of mRNA and the functional FcR investigated. The receptor is a 301 amino acid transmembrane glycoprotein with two homologous extracellular domains that are also homologous to members of the Ig superfamily. The receptor has four sites of N-linked glycosylation and a long 94 amino acid cytoplasmic tail. Northern analysis, immune complex binding, and serological studies demonstrate that the receptor encoded by the cDNA clone binds mouse IgG1/2b and rabbit IgG complexes. 相似文献
63.
64.
Pertussis toxin inhibits CAMP-induced desensitization of adenylate cyclase in Dictyostelium discoideum 总被引:2,自引:0,他引:2
B. Ewa Snaar-Jagalska Peter J. M. Van Haastert 《Molecular and cellular biochemistry》1990,92(2):177-189
cAMP binds to surface receptors of Dictyostelium discoideum cells, transducing the signal to adenylate cyclase, guanylate cyclase and to chemotaxis. The activation of adenylate cyclase is maximal after 1 min and then declines to basal levels due to desensitization, which is composed of two components: a rapidly reversible adaptation process, and a slowly reversible down-regulation of cAMP receptors. Adaptation is correlated with receptor phosphorylation.The chemotactic response and the cAMP-induced cGMP response were not significantly altered in D. discoideum cells pretreated with pertussis toxin. The initial increase of cAMP levels was identical in control and toxin treated cells, suggesting that activation of adenylate cyclase was also not affected. However, cAMP synthesis continued in toxin treated cells, due to a strongly diminished desensitization. Pertussis toxin inhibited the adaptation of adenylate cyclase stimulation, but not the down-regulation or phosphorylation of the cAMP receptors. Adenylate cyclase in D. discoideum membranes can be stimulated or inhibited by GTP, depending on the conditions used. Pertussis toxin did not affect the stimulation of adenylate cyclase but nullified the inhibition. In membranes from desensitized control cells, stimulation of adenylate cyclase by GTP was lost, whereas inhibition was retained. Stimulation of adenylate cyclase in membranes from desensitized pertussis toxin treated cells was diminished but not absent. These results indicate that receptor phosphorylation is not sufficient for adaptation of adenylate cyclase, and that a pertussis toxin substrate, possibly Gi, is also involved in this process.Abbreviations used ATPS
Adenosine 5-0-(3-Thiotriphosphate)
- GTPS
Guanosine 5-0-(3-thiotri-phosphate)
- (Sp)-cAMPS
Adenosine 3,5-monophosphorothioate-Sp-isomer
- dcAMP
2-deoxyadenosine 3,5-monophosphate
- Hepes
N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid
- DTT
Dithiothreitol
- buffer A
10 mM KH2PO4/Na2HPO4, pH 6.5
- buffer B
40 mM Hepes/NaOH, 0.5 mM EDTA, 250 mM sucrose, pH 7.7 相似文献
65.
Ewa Kosior-Jarecka Urszula ?ukasik Dominika Wróbel-Dudzińska Janusz Kocki Joanna Bartosińska Agnieszka Witczak Gra?yna Chodorowska Jerzy Mosiewicz Tomasz ?arnowski 《PloS one》2016,11(1)
Aim
The purpose of this study was to evaluate the influence of polymorphisms of the eNOS gene on the clinical status of patients with normal and high tension glaucoma.Methods
266 Polish Caucasian patients with primary open angle glaucoma were studied. Of the 266, 156 had normal tension glaucoma (NTG) and 110 high tension glaucoma (HTG). DNA material was isolated from peripheral venous blood using commercial kits. Real-time PCR reaction was used to amplify the promoter site of the endothelial nitric oxide synthase (eNOS) gene, including the single nucleotide polymorphism (SNP) site T-786C and part of the 7th exon of eNOS, including G894T SNP. Genotypes were determined with TaqMan SNP Genotyping Assays.Results
There were no significant differences in frequencies of the allelic variants of both polymorphisms. In G894T SNP, however, the wild GG form was more common in the HTG group. The SNP of the eNOS gene did not significantly influence the progression rate in either of the groups studied. There were no differences in variants of the eNOS gene regarding the necessity for and success of surgery and the progression of the disease. In the NTG group, no statistical correlation was observed between G894T, T786C polymorphism variants, and risk factors such as optic disc haemorrhages, optic disc notches, and peripapillary atrophy. Mean diastolic and systolic pressure during the day and night were lowest in NTG patients with the CC variant of the T786C polymorphism. No statistical correlation was observed between the G894T and T786C polymorphisms and capillaroscopic examination results.Conclusions
Genotype frequencies are similar for both the eNOS G894T and T-786C polymorphisms in NTG and HTG patients. These polymorphisms do not correlate with risk factors and do not influence the state of the capillary system in NTG patients. Systolic blood pressure is lower in NTG patients with mutated alleles of both polymorphisms. 相似文献66.
Püsküllüoglu M Lukasiewicz E Miekus K Jarocha D Majka M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2010,48(4):671-677
Rhabdomyosarcoma (RMS) represents the most common sarcoma of soft tissue among children. Two main RMS subtypes are alveolar (ARMS) and embryonal (ERMS). The major goal of this study was to find differentially expressed genes between RMS subtypes that could explain higher metastatic potential in ARMS and would be useful for the differential diagnosis. Using RQ-PCR analysis we compared expression of Snail1 and Snail-related genes among 7 ARMS and 8 ERMS patients' samples obtained from the primary tumors and among 2 alveolar and 2 embryonal cell lines. Our results show that Snail1 is highly expressed both in ARMS patients' samples and the alveolar cell lines. We also found that the expression of E-Cadherin was downregulated and the expression of Matrix Metalloproteinases 2 and 9 (MMP-2 and MMP-9) was upregulated in ARMS. We assume that, as in many tumors, also in RMS Snail1 acts as a regulator for pathways known for their role in cells' metastasis and that Snail1 activity results in increased MMPs and decreased E-Cadherin expression. Our findings may explain higher ARMS aggressiveness. Moreover, we suggest that further studies should be performed to verify if Snail1 can be considered as a potential target for ARMS therapy. 相似文献
67.
68.
O. Akinbo M. T. Labuschagne J. Marín C. Ospina L. Santos E. Barrera J. Gutiérrez F. Ewa E. Okogbenin M. Fregene 《Tropical plant biology》2012,5(2):161-172
Root protein content of elite cassava is very low, largely due to breeder’s selection for other agronomic traits mainly fresh
weight yield and disease resistance. Increased protein content in the root of cassava will improve its usefulness as a more
complete food source in the developing world. An inter-specific F1 hybrid CW 198 - 11 was earlier developed at International Center for Tropical Agriculture (CIAT), Cali, Colombia by genetic
crosses of OW 230 - 1 (FLA 441 - 5) and CW 30–65 (an inter-specific hybrid between an improved cassava variety SG 427 - 87
and an accession of Manihot esculenta ssp flabellifolia (MESCFLAX – 80)). The inter-specific cross was ‘backcrossed’, in the sense of another cross to cassava (MTAI – 8) to generate
a B1P2 family with 225 progenies in which major quantitative trait loci (QTL) for root protein in the backcross population of cassava
were identified. A linkage map from the female parent of the backcross population was used for QTL detection. A total of three
QTL (protg.7, protg.13 and protg.23) controlling protein were identified in three different environments. One QTL was expressed across all three environments.
These results demonstrated high broad sense heritability of 61.6% for protein over 2 years, in two different locations. The
individual effects of alleles at these QTL explained from 15% to 25% of the phenotypic variance. The consistency of QTL controlling
protein across environments reveals their potential for use in marker-assisted recurrent selection. 相似文献
69.
Ewa Bie? Joanna Zima Dorota Wójtowicz Bo?ena Wojciechowska-Maszkowska Krzysztof Kr?cisz Micha? Kuczyński 《PloS one》2014,9(4)
To evaluate postural control and performance in subjects with Down syndrome (SwDS), we measured postural sway (COP) in quiet stance in four 20-second tests: with eyes open or closed and on hard or foam surface. Ten SwDS and eleven healthy subjects participated, aged 29.8 (4.8) and 28.4 (3.9), respectively. The time-series recorded with the sampling rate of 100 Hz were used to evaluate postural performance (COP amplitude and mean velocity) and strategies (COP frequency, fractal dimension and entropy). There were no intergroup differences in the amplitude except the stance on foam pad with eyes open when SwDS had larger sway. The COP velocity and frequency were larger in SwDS than controls in all trials on foam pad. During stances on the foam pad SwDS increased fractal dimension showing higher complexity of their equilibrium system, while controls decreased sample entropy exhibiting more conscious control of posture in comparison to the stances on hard support surface. This indicated that each group used entirely different adjustments of postural strategies to the somatosensory challenge. It is proposed that the inferior postural control of SwDS results mainly from insufficient experience in dealing with unpredictable postural stimuli and deficit in motor learning. 相似文献
70.
Deschner J Wypasek E Ferretti M Rath B Anghelina M Agarwal S 《Journal of biomechanics》2006,39(10):1796-1803
OBJECTIVE: We sought to determine whether fibrochondrocytes from menisci express receptor activator of NF-kappaB (RANK), its ligand (RANKL), or osteoprotegerin (OPG) and, if so, whether their expression is modulated by dynamic mechanical loading under inflammatory and normal conditions. METHODS: Fibrochondrocytes from rat menisci were subjected to cyclic tensile strain (CTS) at various magnitudes and frequencies in the presence or absence of interleukin (IL)-1beta for up to 24 h. In order to determine whether a possible regulatory effect of mechanical loading on RANKL and its receptors under inflamed conditions is sustained, cells were stimulated with IL-1beta for 24 h while being subjected to CTS only for the initial 4 and 8h, respectively. Regulation of RANKL, RANK, and OPG expression and synthesis were determined by semiquantitative and real-time PCR, Western blotting, and immunofluorescence. RESULT: Fibrochondrocytes constitutively expressed low levels of RANKL and RANK but marked levels of OPG. IL-1beta upregulated expression and synthesis of RANKL and RANK significantly (p<0.05), whereas expression of OPG was unaffected following 4 and 24 h. When fibrochondrocytes were simultaneously subjected to CTS and IL-1beta, expression of RANKL and RANK was significantly (p<0.05) downregulated as compared to that of IL-1beta-stimulated unstretched cells. The inhibitory effect of CTS on the IL-1beta-induced upregulation of RANKL and RANK was sustained as well as magnitude and frequency dependent. CONCLUSIONS: Our study provides evidence that RANKL and its receptors are expressed in fibrochondrocytes from meniscus. These data also demonstrate that dynamic mechanical loading can modify the expression of RANKL and RANK in inflammatory conditions. 相似文献