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681.
Ito A Saito S Masuko T Oh-Eda M Matsuura T Satoh M Nejad FM Enomoto T Orikasa S Hakomori SI 《Glycoconjugate journal》2001,18(6):475-485
Renal cell carcinoma (RCC) has been characterized by high expression of three types of disialogangliosides: two based on lacto-series type 1 structure (disialosyl Lc4, GalNAc disialosyl Lc4), the other based on globo-series structure (disialosyl globopentaosylceramide; disialosyl Gb5). The present study established a mAb, 5F3, directed to disialosyl Gb5. 5F3 was established after immunization with RCC cell line ACHN. The major disialoganglioside antigen isolated from ACHN cells, showing specific reactivity with 5F3, was characterized unequivocally as disialosyl Gb5 (V3NeuAcIV6NeuAcGb5) by identification of the core structure as globopentaosylceramide (Gb5) after enzymatic and acid hydrolysis, and by 2-dimensional 1H-NMR spectroscopy. 5F3 does not react with monosialosyl Gb5 (V3NeuAcGb5), Gb5, or any lacto-series structures. 5F3 strongly stained 19 of 41 cases of primary RCC tissue. It reacted with proximal tubules (but not distal tubules) of kidney, microglial cells of cerebrum and cerebellum, goblet cells of stomach and intestine, smooth muscle of various organs. It did not react with parenchymatous cells of various organs, except for kidney epithelia and prostate stroma. Immunostaining of RCC tissue by mAb 5F3, in combination with staining by other antibodies directed to globo-series and lacto-series structures, has prognostic significance in defining metastatic potential of RCC. 相似文献
682.
Kouhpayeh HR Hashemi M Hashemi SA Moazeni-Roodi A Naderi M Sharifi-Mood B Taheri M Mohammadi M Ghavami S 《Genetics and molecular research : GMR》2012,11(2):1075-1081
The protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene, which encodes an intracellular lymphoid-specific phosphatase, is considered an important regulator of T-cell activation. We investigated a possible association between the PTPN22 C1858T (R620W) polymorphism and pulmonary tuberculosis in an Iranian population. Single nucleotide polymorphisms of PTPN22 C1858T (rs2476601) were genotyped in 172 pulmonary tuberculosis cases and 204 normal subjects from Zaheden, Iran. Frequencies of genotypes CC, CT and TT of the PTPN22 C1858T polymorphism were 98.3, 1.7 and 0% in the pulmonary tuberculosis patients, and 96.1, 3.9 and 0% in the control group, respectively (P = 0.239). The frequency of the minor (T) allele was 0.8% in pulmonary tuberculosis patients and 2.0% in controls. Significant differences were not observed in genotype or allele frequencies of PTPN22 C1858T in the comparison between pulmonary tuberculosis patients and healthy subjects in our Iranian population sample. 相似文献
683.
Khamesipour A Nateghi Rostami M Tasbihi M Miramin Mohammadi A Shahrestani T Sarrafnejad A Sohrabi Y Eskandari SE Keshavarz Valian H 《Microbes and infection / Institut Pasteur》2012,14(9):702-711
Recovery from CL is usually accompanied with long-lasting protection and induction of strong immune response. The phenotypes, generation and maintenance of central (=TCM) and effector (=TEM) memory T cell subsets in human leishmaniasis are not well known. Profile of T cell subsets were analyzed on peripheral CD8+ T cells from volunteers with history of cutaneous leishmaniasis (HCL).In HCL and control groups, mean frequencies of CCR7+CD45RA+CD8+ naïve and CCR7?CD45RA?CD8+ TEM cells were higher than other subsets before culture, but after stimulation with soluble Leishmania antigen, the frequency of naïve T cells was significantly decreased and the frequency of TEM cells was significantly increased. TEM phenotype composed the highest portion of proliferating Carboxy Fluorescein diacetate Succinimidyl Ester (CFSE)-dim population which was significantly higher in HCL volunteers than in control group. Stimulation of isolated CD8+ memory T cells, but not naïve T cells, from HCL volunteers induced a significantly higher IFN-γ production compared with that of healthy controls. Intracellular IFN-γ staining provided the same result.Memory population is shown to be responsible for Leishmania-induced IFN-γ production. Leishmania-reactive proliferating TEM cells were identified as the most frequent subset which may play a role in recall immune response and protection against Leishmania infection. 相似文献
684.
Nateghi Rostami M Douraghi M Miramin Mohammadi A Nikmanesh B 《European cytokine network》2012,23(2):64-67
There are reports showing that pro-inflammatory cytokines are dysregulated in patients with Down's syndrome (DS). However, most of these reports concern adults. We analyzed cytokine levels in serum samples from children with DS, and compared them with samples from intellectually disabled (ID), and healthy, control children. Blood samples were collected from 24 DS, 24 age-/sex-matched ID, and 24 age-/sex-matched healthy, control children. Serum levels of the cytokines IL-5, IL-10, IL-13, IFN-γ, and TNF-α were measured using a sandwich ELISA method, . The age range of the children was 1-15 years, with a mean ± SD of 5.75 ± 4.36 years. TNF-α levels were significantly higher in the DS and ID groups compared with those found in healthy, control children (P<0.05). The DS and ID groups had significantly higher IFN-γ levels compared with healthy, control children (P = 0.0002 and P<0.01, respectively), with significant higher levels in the DS than the ID group (P<0.05). Serum from the ID group showed significantly higher IL-10 levels compared with those from the DS group (P<0.05), but not the healthy, control group. Significant correlations were found between the differences in TNF-α and IFN-γ levels, in both ID (rs = 0.558; P = 0.005) and DS children (rs = 0.405; P<0.05). There were no significant differences found in serum levels of IL-13 between the groups, and IL-5 was not detectable in any of the serum samples. Levels of TNF-α and IFN-γ were increased, and IL-10 decreased in serum from children with DS. It may be that these differences contribute to the clinical symptoms seen in DS: consequently, these pro-inflammatory cytokines might be useful as early biomarkers of the disorders associated with DS. 相似文献
685.
Hamedi-Asl P Halabian R Bahmani P Mohammadipour M Mohammadzadeh M Roushandeh AM Jahanian-Najafabadi A Kuwahara Y Roudkenar MH 《Cell stress & chaperones》2012,17(2):181-190
The capacity of mesenchymal stem cells (MSCs) to survive and engraft in the target tissue may lead to promising therapeutic
effects. However, the fact that the majority of MSCs die during the first few days following transplantation complicates cell
therapy. Hence, it is necessary to strengthen the stem cells to withstand the rigors of the microenvironment to improve the
efficacy of cell therapy. In this study, we manipulated MSCs to express a cytoprotective factor, heme oxygenase-1 (HO-1),
to address this issue. Full-length cDNA of human HO-1 was isolated and cloned into TOPO vector by TOPO cloning reaction. Then,
the construct was ligated to gateway adapted adenovirus expression vector by LR recombination reaction. Afterwards, the recombinant
virus expressing HO-1 was produced in appropriate mammalian cell line and used to infect MSCs. The HO-1 engineered MSCs were
exposed to hypoxic and oxidative stress conditions followed by evaluation of the cells’ viability and apoptosis. Transient
expression of HO-1 was detected within MSCs. It was observed that HO-1 expression could protect MSCs against cell death and
the apoptosis triggered by hypoxic and oxidative stress conditions. The MSCs-HO-1 retained their ability to differentiate
into adipogenic, chondrogenic, or osteogenic lineages. These findings could be applied as a strategy for prevention of graft
cell death in MSCs-based cell therapy and is a good demonstration of how an understanding of cellular stress responses can
be used for practical applications. 相似文献
686.
Bakhtiari R Mohammadi Sephavand N Nili Ahmadabadi M Nadjar Araabi B Esteky H 《Journal of computational neuroscience》2012,33(2):389-404
Impairments in attentional behaviors, including over-selectivity, under-selectivity, distractibility and difficulty in shift of attention, are widely reported in several developmental disorders, including autism. Uncharacteristic inhibitory to excitatory neuronal number ratio (IER) and abnormal synaptic strength levels in the brain are two broadly accepted neurobiological disorders observed in autistic individuals. These neurobiological findings are contrasting and their relation to the atypical attentional behaviors is not clear yet. In this paper, we take a computational approach to investigate the relation of imbalanced IER and abnormal synaptic strength to some well-documented spectrum of attentional impairments. The computational model is based on a modified version of a biologically plausible neural model of two competing minicolumns in IT cortex augmented with a simple model of top-down attention. Top-down attention is assumed to amplify (attenuates) attended (unattended) stimulus. The inhibitory synaptic strength parameter in the model is set such that typical attentional behavior is emerged. Then, according to related findings, the parameter is changed and the model's attentional behavior is considered. The simulation results show that, without any change in top-down attention, the abnormal inhibitory synaptic strength values - and IER imbalance- result in over-selectivity, under-selectivity, distractibility and difficulty in shift of attention in the model. It suggests that the modeled neurobiological abnormalities can be accounted for the attentional deficits. In addition, the atypical attentional behaviors do not necessarily point to impairments in top-down attention. Our simulations suggest that limited changes in the inhibitory synaptic strength and variations in top-down attention signal affect the model's attentional behaviors in the same way. So, limited deficits in the inhibitory strength may be alleviated by appropriate change in top-down attention biasing. Nevertheless, our model proposes that this compensation is not possible for very high and very low values of the inhibitory strength. 相似文献
687.
The gene encoding proline dehydrogenase (ProDH) from Pseudomonas fluorescence was isolated using PCR amplification and cloned into pET23a expression vector. The expression of the recombinant target enzyme was induced by addition of IPTG. The produced His-fusion enzyme was purified and its kinetic properties were studied. The 3D structure modeling was also performed to identify key amino acids involved in FAD-binding and catalysis. The PCR product contained a 1033 bp open reading frame encoding 345 amino acid residue polypeptide chain. SDS-PAGE analysis revealed a MW of 40 kDa, whereas the native enzyme exhibited a MW of 40 kDa suggesting a monomeric protein. The K(m) and V(max) values of the P. fluorescence ProDH were estimated to be 35 mM and 116 micromol/min, respectively. ProDH activity was stable at alkaline pH and the highest activity was observed at 30 degrees C and pH 8.5. The modeling analysis of the three dimensional structure elucidated that Lys-173 and Asp-202, which were oriented near the hydroxyl group of the substrate, were essential residues for the ProDH activity. This study, to our knowledge, is the first data on the cloning and biochemical and structural properties of P. fluorescence ProDH. 相似文献
688.
Comparison of fructan dynamics in two wheat cultivars with different capacities of accumulation and remobilization under drought stress 总被引:1,自引:0,他引:1
Joudi M Ahmadi A Mohamadi V Abbasi A Vergauwen R Mohammadi H Van den Ende W 《Physiologia plantarum》2012,144(1):1-12
Remobilization of stored carbohydrates in the stem of wheat plants is an important contributor to grain filling under drought stress (DS) conditions. A massive screening on Iranian wheat cultivars was performed based on stem dry weight changes under well-watered and DS conditions. Two cultivars, Shole and Crossed Falat Hamun (CFH), with different fructan accumulation and remobilization behavior were selected for further studies. Water-soluble carbohydrates (WSCs) and fructan metabolizing enzymes were studied both in the stem penultimate and in sucrose (Suc) treated, excised leaves. Under drought, CFH produced higher grain yields than Shole (412 vs 220 g m(-2)). Also, grain yield loss under drought was more limited in CFH than in Shole (17 vs 54%). Under drought, CFH accumulated more graminan-type fructo-oligosaccharides than Shole. After anthesis, fructan 6-exohydrolase (6-FEH; EC 3.2.1.154) activities increased more prominently than fructan 1-exohydrolase (EC 3.2.1.153) activities during carbon remobilization. Interestingly, CFH showed higher 6-FEH activities in the penultimate than Shole. The field experiment results suggest that the combined higher remobilization efficiency and high 6-FEH activities in stems of wheat could contribute to grain yield under terminal drought. Similar to the penultimate, fructan metabolism differed strongly in Suc-treated detached leaves of selected cultivars. This suggests that variation in the stem fructan among wheat cultivars grown in the field could be traced by leaf blade induction experiments. 相似文献
689.
Kalinina J Dutta K Ilghari D Beenken A Goetz R Eliseenkova AV Cowburn D Mohammadi M 《Structure (London, England : 1993)》2012,20(1):77-88
Uncontrolled fibroblast growth factor (FGF) signaling can lead to human malignancies necessitating multiple layers of self-regulatory control mechanisms. Fibroblast growth factor receptor (FGFR) autoinhibition mediated by the alternatively spliced immunoglobulin (Ig) domain 1 (D1) and the acid box (AB)-containing linker between D1 and Ig domain 2 (D2) serves as the first line of defense to minimize inadvertent FGF signaling. In this report, nuclear magnetic resonance and surface plasmon resonance spectroscopy are used to demonstrate that the AB subregion of FGFR electrostatically engages the heparan sulfate (HS)-binding site on the D2 domain in cis to directly suppress HS-binding affinity of FGFR. Furthermore, the cis electrostatic interaction sterically autoinhibits ligand-binding affinity of FGFR because of the close proximity of HS-binding and primary ligand-binding sites on the D2 domain. These data, together with the strong amino acid sequence conservation of the AB subregion among FGFR orthologs, highlight the universal role of the AB subregion in FGFR autoinhibition. 相似文献
690.